Thermo-Loc is a special reusable polymer material that is rigid at room temperature yet becomes pliable when heated or warmed. Developed to hold irregularly shaped or fragile items, Thermo-Loc can be used on firearms, knives, wood, and more. Just follow these basic steps: heat, form, and hold. Supplied in convenient 6" (150 mm) long sticks, Thermo-Loc is a medium gray color designed to reduce eye strain under work lights. It is non-toxic and biodegradable.