Genuine latex Foam Rubber is the best material available to protect the delicate radio equipment inside your R/C models. Loosely wrapped around the receiver and battery pack, FOAM RUBBER can keep harmful engine vibrations from causing a serious radio "glitch". Also helps protect the receiver and battery from shock damage in the event of a crash. Model boats need it to prevent the constant pounding of the water against the hull from causing trouble. Size: 1/2 x 8 x 12"