This is a three-pack of Z3 Grease Pack from Mad Water. It is used to restore the flexibility, suppleness and glide of all elastomers (rubber), metals, and plastics, including polyurethane, natural rubber, and neoprene. It is generally used seasonally but if you use your gear with greater frequency, more application may be required. This is a non-toxic, non-flammable substance that guards against damage from UV rays, acid rain and saltwater.