How to Use a Handcuff Key Pen in the Field

By Training Videos | UsingASPBatons | asp-usa.com | Published: 2026-10-21

Category: How-to Guides

Learn how to deploy a handcuff key pen during duty, from proper grip to one-handed operation, plus common mistakes to avoid.

Quick Answer

Use a handcuff key pen by gripping it like a standard pen, aligning the key bit with the handcuff keyhole, and turning smoothly while maintaining control of the subject's restraint arm.

Why a Pen Key Works Better Than a Loose Key

A loose handcuff key can be hard to locate under stress, especially in a duty bag or pocket. A pen-style key like the LockWrite Pen Key keeps the key accessible and gives you a larger handle for better torque and control.

The trade-off is that you must train to avoid using the pen for writing after it has been inserted into a restraint, as residue or debris can transfer to the ink cartridge.

Carrying the Pen Key for Quick Access

Clip the pen key to a shirt pocket, duty shirt placket, or inside a vest panel. The clip should face outward so you can retrieve it with either hand. Avoid placing it in a pants pocket where it can be confused with a regular pen.

If you carry a separate clip handcuff key (like the ASP Clip Handcuff Key), keep it in a backup location such as a boot or belt keeper. The pen key is your primary due to its larger grip.

Step-by-Step Field Use

1. Retrieve and Grip the Pen Key: Pull the pen key from its clip with your dominant hand. Grip it as you would a writing pen, with your index finger resting near the tip and your thumb along the barrel. Do not hold it like a fist or dagger—this reduces fine motor control. Common mistake: Gripping too far back on the barrel reduces leverage and makes it harder to feel the keyhole.
2. Locate the Handcuff Keyhole: Use your non-dominant hand to stabilize the subject's restrained arm. Slide your thumb along the handcuff body until you feel the keyhole. On double-lock handcuffs, the keyhole is on the side of the cuff opposite the ratchet. Checkpoint: If the subject is resisting, maintain wrist control with your non-dominant hand before attempting key insertion.
3. Insert the Key Bit Fully: Align the key bit with the keyhole and push it in until it stops. The ASP BackSet feature (on clip keys) helps center the bit; with a pen key, you may need to wiggle slightly if the cuff is old or dirty. Common mistake: Partial insertion can cause the key to slip or strip the internal mechanism, leading to a jam.
4. Turn the Key Smoothly: Rotate the pen key clockwise (for most handcuffs) until you feel the cuff release. Use a steady, continuous motion—jerking can snap a weaker key. If the cuff does not open, check that you are turning the correct direction. Checkpoint: If the key feels stuck, do not force it. Remove, inspect the keyhole for debris, and try again.
5. Secure the Key After Use: Once the cuff is open, remove the pen key and return it to its clip. If you used the pen tip for writing earlier, wipe it clean before clipping it back. Do not leave the key in the cuff—it can be lost or used against you. Common mistake: Setting the key down on a nearby surface increases the chance of misplacing it during a dynamic situation.

Product Facts

LockWrite Pen Key (Twist): The LockWrite Pen Key combines a functional pen with a heat-treated ASP handcuff key made from 4140 steel. You get a writing instrument and a restraint key in one tool, reducing gear clutter while maintaining a durable key that resists breakage.
LockWrite Pen Key (Twist)
Clip Handcuff Key, Black: ASP Clip Handcuff Keys are hammer forged and precision machined, with a unique BackSet feature for rapid keyhole location. If you need a backup key that you can find by feel in low light, the clip design and BackSet feature help you insert the key quickly without looking.
Clip Handcuff Key, Black