PhD Fitness LLC The JYM Strength Bands System, by Renowned Training Expert Dr. Jim Stoppani, Includes 14 Anti-SNAP Bands JYM Strength Bands are dipped in natural latex to provide maximal resistance and durability. Components are super strong and made of the highest quality materials. We use industrial grade materials like molded nylon and ABS for the core of the handles and door anchors, and solid iron for the clips. Every band incorporates anti-snap technology to allow you to work out safely and with the utmost confidence!