3mm thick to protect the lipo from screw heads.
The material is between neoprene and rubber in density. (As used industrially in the mining industry)
Adhesive backed with Venture Tape.
More grip, strength and resistance to crushing than neoprene, and less weight than rubber.
The pad can be cut down to reduce weight in various methods. Cutting the middle allows the lipo strap though, and the front and back can be removed for light weight setups, leaving only a rectangle.