Handcuff shims can open handcuffs by separating the ratcheting mechanism from the lock body and a handcuff's swing arm. Sparrows handcuff shims come with a unique citadel head that offers such extreme grip that the shims can be operated with a single finger. Even with sweaty hands the citadel head prevents your fingers from slipping off the shim.
Works on Smith & Wesson, Peerless, Safariland and countless others