Zak Tool #70B-104 Non-Swivel Handcuff Key for S&W Model 104 Handcuffs. Extra large 4 3/4″ key. This handcuff key does not have a swivel that could break off, just a hole through the center at top. This is preferred for many high security correctional environments. Zak Tool used to make an extended key for the Smith & Wesson Model 104 with a carbon fiber body with pocket clip that was discontinued. The new key is available now at Handcuff Warehouse: Zak 70B-104 Handcuff Key for Smith & Wesson Model 104.