The round swivel handcuff key is a classic design, it has a dimpled sleeve for extra grip and allows hand cuffs to be locked/unlocked with a spin of the thumb and forefinger. It is made of heat treated stainless steel and is designed to provide an indefinite period of service. Additionally it features a standard double locking pin and a large split ring attachment . The steel loop allows it to be attached to your other keys, although it is the perfect length to stow in the pocket of your vest.
The Zak Tools range are manufactured to an extremely high standard. The key and locking pin fit all modern standard Asp, Hiatt and TCH rigid and chain cuffs.
Theres only so much you can say for a handcuff key... but for what this is it is a good key which isn't going to break on you anytime soon. I would recommend use with a chain or set of keys which have something on, as if you just use a clip about 3 inches long like I did, from your waist it can be a bit tricky.