Zak Tool 5in Corrections Hand Cuff Key Black. The key part is heat-treated stainless steel that is flared out at the base for extra strength and then narrows at the end. For greater security in correctional environments there is no swivel that could break off. The 90B handcuff key is 5 1/8 inches long. Specifications for Zak Tool ZT90 5in Corrections Standard Hand Cuff Key: Manufacturer: Zak Tool Handcuff Key Type: Standard Shaft Material: Heat-treated Stainless Steel Body Material: Advanced Lightweight Polymer Color: Black Length: 5.125 in Package Contents: Zak Tool ZT90 5in Corrections Hand Cuff Key Zak Tool ZT90: ZT90 5in Corrections Hand Cuff Key Black