Cobra Cuffs are made with Cross-Linked Rubber and come in 4 standard Colors: Black, Tan, Green & White.  Re-Useable Trainer Cuffs are Blue - For Training Only 

Rubber helps prevent the stress cracking common with nylon zip ties when exposed to cold, heat or creasing. Superior shelf life is an added benefit with Cobra Cuffs (3-5 yrs, depending upon storage conditions)