All the handcuffs we sell at the Handcuff Warehouse have double locks. Across the various manufacturers we deal with there are 3 types of double locks: Slot Lock, Push Pin and Lever Lock. When a set of handcuffs is double locked, they cannot be tightened without disengaging the double lock with a handcuff key.
Slot Lock:
Most Smith & Wesson and all ASP handcuffs feature the slot lock double locking system. For both brands there is a double lock slot on both sides of the cheek plate. To double lock Smith & Wesson slot lock handcuffs insert the double lock pin on your handcuff key into the top of the slot, and pull down towards the keyhole until you feel or hear it click.
To double lock ASP handcuffs insert the pin on your handcuff key into the slot and pull away from the keyhole. You can also double lock ASP handcuffs by inserting the handcuff key into the keyhole and turning they key clockwise.
Slot lock double lock as seen on Smith & Wesson Handcuffs
Push Pin Double Lock:
Push pin double locks are very popular. Advocates of the push pin system say the push pin is easier to use than the slot lock, especially in low light situations. All Peerless, Hiatt, Chicago and CTS handcuffs feature push pin double locks. The push pin on all the different brands of handcuffs is in the same place, the outer top edge of the cuffs right under the double strand. To engage the double lock simply push the double lock pin on your handcuff key into the double lock hole until you hear or feel a click.
Push pin double lock as seen on a pair of Peerless Superlite Handcuffs
Lever Locks:
Smith & Wesson’s M&P lever lock handcuffs are still relatively new to the market having just come out a few years ago. The only US made handcuff with a finger activated double lock. The double lock levers on these handcuffs are located in the same place as the push pin on other cuffs, only you do not need a key to activate the lock. Simply use your finger to pull the lever up and away from the keyhole until you hear or feel the click of the lock activating.
Finger activated lever lock