Assisted Opening Knives

Assisted Opening Knives

shrade assisted opening knife image

An assisted-opening knife is a type of folding knife which uses an internal mechanism to finish the opening of the blade once the user has partially opened it using a flipper or thumb-stud attached to the blade. 

Assisted opening knives merge function and speed to create a mechanism that opens a blade as fast and smooth as a switchblade. The difference between automatic knives and spring assisted knives is how the blade is deployed. An automatic knife deploys the blade on its own (no exterior finger force) with a trigger/button. A spring assisted knife needs an external force to engage the spring. When the knife is in the closed position, the blade is held in place by means of torsion springs and an additional blade lock (optional). As the user applies manual pressure to the thumbstud to open the knife, a mechanism such as a torsion spring moves along a track in the liner and rapidly rotates the blade into the open and locked position.

Other trade names for assisted-opening knives are: Forward Action Spring Technology, A/O Knife, Torsion Assist Knife, Assisted Knife, Spring Assist Knife, Spring Assisted Knife, Quick Release, Quick Draw, Alternative Automatic, Outburst, SpeedSafe, Blade Launcher, S.A.T (SOG Assisted Technology), and the Semi-Auto.

Assisted Opening Knives

active on eBay
Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Notice: Undefined variable: classstring in /home/knifepar/public_html/wp-content/plugins/ebay-feeds-for-wordpress/ebay-feeds-for-wordpress.php on line 77

Kershaw Speedsafe Assisted Opening 8Cr13MoV Dagger Blade Folding Pocket Knife

$28.99
End Date: Thursday Jul-23-2020 11:33:30 PDT
Buy It Now for only: $28.99
Buy It Now | Add to watch list

KERSHAW "ASTEROID" SPEED SAFE SPRING ASSISTED KNIFE RAZOR SHARP BLADE

$25.99
End Date: Sunday Jul-19-2020 15:11:54 PDT
Buy It Now for only: $25.99
Buy It Now | Add to watch list

1660 Kershaw Leek Knife silver plain Blade handle *New Blem* assisted opener

$33.95
End Date: Tuesday Jul-21-2020 21:46:54 PDT
Buy It Now for only: $33.95
Buy It Now | Add to watch list

Kershaw Leek 1660 Ken Onion 3" Knife

$31.99
End Date: Saturday Aug-1-2020 22:11:22 PDT
Buy It Now for only: $31.99
Buy It Now | Add to watch list

Kershaw Leek 1660 pocket Knife, 3 inch Blade, made in USA, assisted opening

$29.99
End Date: Thursday Jul-23-2020 2:18:12 PDT
Buy It Now for only: $29.99
Buy It Now | Add to watch list

CRKT Ruger Crack Shot Assisted Open 8Cr13MoV Blade EDC Folding Pocket Knife NEW

$27.99
End Date: Friday Jul-17-2020 12:57:41 PDT
Buy It Now for only: $27.99
Buy It Now | Add to watch list

Kershaw BlackWash Amplitude Assisted Open 8Cr13MoV Blade Folding Pocket Knife

$27.99
End Date: Saturday Jul-4-2020 13:56:53 PDT
Buy It Now for only: $27.99
Buy It Now | Add to watch list

Gerber Haul Coyote Assisted Open Pocket Knife Folder Button Lock 5Cr15 001680

$36.99
End Date: Monday Aug-3-2020 11:47:41 PDT
Buy It Now for only: $36.99
Buy It Now | Add to watch list

Kershaw 1336 Halogen Black G10/Carbon Fiber Handle Assisted Open Folding Knife

$27.44
End Date: Sunday Aug-2-2020 4:00:54 PDT
Buy It Now for only: $27.44
Buy It Now | Add to watch list

Kershaw 2335 Al Mar AM-3 Black G-10 Assisted Open Satin Finish Plain Edge Knife

$27.32
End Date: Tuesday Jul-28-2020 3:57:44 PDT
Buy It Now for only: $27.32
Buy It Now | Add to watch list

Kershaw 1670BLK Blur Black Handle Plain Edge Assisted Open Folding Pocket Knife

$58.78
End Date: Tuesday Jul-14-2020 3:15:27 PDT
Buy It Now for only: $58.78
Buy It Now | Add to watch list

Kershaw Knives Leek 1660 Ken Onion Plain Edge Assisted Folding Knife 3" Blade

$32.52
End Date: Wednesday Jul-22-2020 20:50:23 PDT
Buy It Now for only: $32.52
Buy It Now | Add to watch list

KERSHAW TANTO BLUR BLACKWASH ASSISTED OPENING KNIFE 1670TSTBW (NEW) #B1

$50.00
End Date: Sunday Aug-2-2020 18:23:04 PDT
Buy It Now for only: $50.00
Buy It Now | Add to watch list

1660 Kershaw Leek Pocket Knife, 3 inch Blade-IN BOX-New

$31.53
End Date: Tuesday Jul-28-2020 1:36:10 PDT
Buy It Now for only: $31.53
Buy It Now | Add to watch list

Kershaw Dividend Folding Knife 420HC Steel Blade Gray Anodized Aluminum Handle

$46.99
End Date: Wednesday Jul-29-2020 11:04:41 PDT
Buy It Now for only: $46.99
Buy It Now | Add to watch list

1600 Kershaw Chive NEW FLAG LOGO Knife plain Blade 3" frame lock New *Blem* A/O

$29.95
End Date: Tuesday Jul-21-2020 21:48:27 PDT
Buy It Now for only: $29.95
Buy It Now | Add to watch list

CRKT Flat Out Assisted Open 8Cr13MoV Blade Everyday Carry Folding Pocket Knife

$39.99
End Date: Friday Jul-17-2020 9:56:19 PDT
Buy It Now for only: $39.99
Buy It Now | Add to watch list

8.5" TAC FORCE ASSISTED OPEN TACTICAL FOLDING KNIFE GLASS BREAKER Blade Pocket

$29.95
End Date: Saturday Jul-4-2020 18:56:45 PDT
Buy It Now for only: $29.95
Buy It Now | Add to watch list

1620TEAL Kershaw Scallion Knife plain blade 1620 *New Blem* Speed Safe USA Made

$39.95
End Date: Thursday Jul-30-2020 15:28:11 PDT
Buy It Now for only: $39.95
Buy It Now | Add to watch list

1812 Kershaw Dividend Folding Pocket Knife Assisted Opening Plain Stonewashed

$32.95
End Date: Friday Jul-24-2020 16:05:47 PDT
Buy It Now for only: $32.95
Buy It Now | Add to watch list

8100 Kershaw Funxion EMT pocket knife knives Assisted opener

$28.95
End Date: Thursday Jul-16-2020 12:22:10 PDT
Buy It Now for only: $28.95
Buy It Now | Add to watch list

Kershaw Emerson 3560 Ember Stainless Handle Assisted Open Folding Pocket Knife

$25.95
End Date: Sunday Jul-5-2020 5:26:57 PDT
Buy It Now for only: $25.95
Buy It Now | Add to watch list

1660RDBW Kershaw Leek Pocket knife plain Blade Exclusive A/O NewBlem FLAG LOGO

$42.95
End Date: Sunday Aug-2-2020 17:38:32 PDT
Buy It Now for only: $42.95
Buy It Now | Add to watch list

1776GRYBW Kershaw Link Drop Point pocket knife assisted opening New Blem USA

$41.95
End Date: Thursday Jul-16-2020 13:54:15 PDT
Buy It Now for only: $41.95
Buy It Now | Add to watch list

Kershaw "usa" - Link M390 STEEL Blade Spring Assist Flipper knife KAI 1776BLK

$105.00
End Date: Friday Jul-24-2020 3:32:16 PDT
Buy It Now for only: $105.00
Buy It Now | Add to watch list

Kershaw Scrambler 8Cr13MoV Assisted Opening Blackwash Blade Folding Pocket Knife

$28.99
End Date: Sunday Jul-26-2020 14:01:30 PDT
Buy It Now for only: $28.99
Buy It Now | Add to watch list

CRKT Ruger Crack Shot Assisted Opening 8Cr13MoV Blade Folding Pocket EDC Knife

$26.99
End Date: Saturday Jul-11-2020 8:55:54 PDT
Buy It Now for only: $26.99
Buy It Now | Add to watch list

Mossberg™ Pocket Knife Assisted Opening Liner Lock Folding Stainless Blade NEW

$28.95
End Date: Tuesday Jul-21-2020 21:32:02 PDT
Buy It Now for only: $28.95
Buy It Now | Add to watch list

Gil Hibben Fast EDC Ball Bearing Assisted Opening Hurricane Folding Pocket Knife

$44.73
End Date: Friday Jul-10-2020 8:50:17 PDT
Buy It Now for only: $44.73
Buy It Now | Add to watch list

Spyderco Byrd Folding Knife 3.75" Part Serrated 8Cr13MoV Stainless Steel Blade

$35.70
End Date: Sunday Aug-2-2020 7:03:01 PDT
Buy It Now for only: $35.70
Buy It Now | Add to watch list

KERSHAW 1605 Clash SpeedSafe Assisted Opening (8Cr13MoV) Plain Edge Pocket Knife

$28.00
End Date: Friday Jul-10-2020 9:13:24 PDT
Buy It Now for only: $28.00
Buy It Now | Add to watch list

Kershaw Vedder TiCN Coated 8Cr13MoV Blade Assisted Opening Folding Pocket Knife

$29.99
End Date: Saturday Jul-4-2020 13:57:24 PDT
Buy It Now for only: $29.99
Buy It Now | Add to watch list

NEW WHOLESALE LOT 25 PCS TACTICAL ASSORTED SPRING FOLDING ASSISTED POCKET KNIFE

$89.99
End Date: Thursday Jul-16-2020 4:57:44 PDT
Buy It Now for only: $89.99
Buy It Now | Add to watch list

* 1810 Kershaw Intellect pocket knife plain edge Assisted Opener knives NIB New

$26.95
End Date: Tuesday Jul-14-2020 20:05:44 PDT
Buy It Now for only: $26.95
Buy It Now | Add to watch list

Kershaw - MISDIRECT Spring Assist Flipper Knife w/ Frame-Lock blackwash KAI 1365

$25.95
End Date: Sunday Jul-12-2020 11:25:02 PDT
Buy It Now for only: $25.95
Buy It Now | Add to watch list

# 1551ti Kershaw Median Cabela's Excl folding pocket knife assisted opener NEW

$25.95
End Date: Sunday Jul-19-2020 12:21:06 PDT
Buy It Now for only: $25.95
Buy It Now | Add to watch list

1660OLBW Kershaw Leek Knife plain Blade Olive handle *New Blem* assisted opener

$42.95
End Date: Saturday Jul-25-2020 11:50:49 PDT
Buy It Now for only: $42.95
Buy It Now | Add to watch list

KERSHAW "WILDEN" SPEED SAFE ASSISTED OPEN KNIFE RAZOR SHARP BLADE

$25.99
End Date: Sunday Jul-19-2020 16:59:20 PDT
Buy It Now for only: $25.99
Buy It Now | Add to watch list

5.11 RFA Assisted Open Tanto Pocket Knife CPM S30V 51092 FRN Black 8.40" Open

$44.75
End Date: Wednesday Jul-15-2020 11:59:07 PDT
Buy It Now for only: $44.75
Buy It Now | Add to watch list

Cold Steel Luzon Folding Extra Large Knife 6" 8Cr13MoV Blade Black GFN Handle

$52.49
End Date: Tuesday Jul-7-2020 13:57:02 PDT
Buy It Now for only: $52.49
Buy It Now | Add to watch list

KERSHAW 1365 Misdirect Stainless Handle Reverse Tanto Assisted Open Knife

$25.89
End Date: Saturday Aug-1-2020 6:01:03 PDT
Buy It Now for only: $25.89
Buy It Now | Add to watch list

Kershaw "usa" - Link CPM-20CV STEEL Blade Spring Assist Flipper knife 1776OLSW

$79.50
End Date: Friday Jul-10-2020 14:18:46 PDT
Buy It Now for only: $79.50
Buy It Now | Add to watch list

Kershaw Misdirect Gray Assisted Open Framelock Folding Pocket Knife 1365

$26.84
End Date: Sunday Jul-26-2020 14:21:39 PDT
Buy It Now for only: $26.84
Buy It Now | Add to watch list

Kershaw Assisted Opening Spline Blackwash 8Cr13MoV Blade Framelock Folding Knife

$25.99
End Date: Saturday Jul-25-2020 13:44:11 PDT
Buy It Now for only: $25.99
Buy It Now | Add to watch list

8.5" PUNISHER WAR ZONE SKULL ASSISTED OPEN FOLDING POCKET KNIFE SPRING Blade New

$29.95
End Date: Saturday Jul-4-2020 18:31:35 PDT
Buy It Now for only: $29.95
Buy It Now | Add to watch list

Smith & Wesson M&P Dual Action Magic Assisted Pocket Knife Aus-8 7 1/2" Open New

$29.99
End Date: Wednesday Jul-15-2020 12:10:43 PDT
Buy It Now for only: $29.99
Buy It Now | Add to watch list

Shinwa Saihon Assisted Open Recurve Cleaver Pocket Knife 1062 G10 8.50" Open New

$25.49
End Date: Sunday Jul-5-2020 13:46:51 PDT
Buy It Now for only: $25.49
Buy It Now | Add to watch list

ALBATROSS Ball Bearing Assisted Open Pocket Folding Knife D2 Blade G10 Handle

$27.50
End Date: Sunday Jul-5-2020 22:53:44 PDT
Buy It Now for only: $27.50
Buy It Now | Add to watch list

Assisted Opening Knife Reviews

More About Assisted Opening Knives

A common source of confusion for new knife enthusiasts is the difference between a spring assisted knife and a switchblade knife. Even those who are familiar with pocket knives or fixed blade knives often don’t know the difference between a switchblade and an assisted knife. The confusion is easy to understand as in both cases the knife may seem to release from the handle on its own. But when you look more closely at the mechanisms which open each blade, you can quickly see the difference.

Although commonly confused with switchblade knives, a switchblade can be opened automatically simply with the push of a button, but the user of an assisted-opening knife must open it about one-quarter of the way (45°) before the mechanism opens the knife the rest of the way. The difference is important legally; because the blade does not open simply "by the push of a button or by force of gravity" the assisted-opening knife is typically not considered a switchblade, and may escape the restrictions applying to those in many places.

The switchblade, or automatic knife, has a button or a lever which releases the blade. The button or lever releases the tension held by a spring inside the knife handle. When the lever or button is pushed, the tension from the spring releases and launches the blade from the handle and into a locked position. Some switchblades release the blade from the side of the handle like a spring assisted or a folding knife, while others release out the front of handle (Out-the-Front or OTF).  There are very strict laws concerning the ownership and carry of automatic knives, and you should always check local regulations before purchasing to avoid problems.

The spring assisted knife, or assisted opening knife, doesn’t rely on a button or lever for opening. Instead, it uses a spring or torsion bar which doesn’t engage until the knife blade has opening momentum from another source. The best source is obviously human power engaging a thumb stud, thumb hole, thumb disc, or flipper, moving the blade forward until the spring or torsion bar engages and moves the blade open the rest of the way.

The simplest way to tell the difference is whether or not there is a button or lever. An assisted opening knife does not have a button or lever. It has some form of initializing action that requires human effort. Your thumb has to push on a flipper, a thumb stud, a thumb disc, or a thumb hole to start moving the blade. If there is a push button or a slide that releases the blade, that makes it an automatic.

The first assisted opening knife was designed by Blackie Collins in 1995 and was named the "Strut-and-Cut"; it was based on the strut of his Ducati motorcycle. A similar concept was developed three years later by knifemaker Ken Onion with Onion's idea based on a similar mechanism in his Harley Davidson motorcycle. Onion applied for a patent on his design in 1998.


Notice: compact(): Undefined variable: limits in /home/knifepar/public_html/wp-includes/class-wp-comment-query.php on line 853

Notice: compact(): Undefined variable: groupby in /home/knifepar/public_html/wp-includes/class-wp-comment-query.php on line 853