The Speed Rail Mounting Suction Cup  from Tilta is a high-capacity suction cup designed with sturdy aluminum, stainless steel, and rubber to sustain payloads up to 110 lb. It works perfectly with the Tilta Speed Rail Car Mounting Kit but is compatible with any 50mm speed rail. When used with other Suction Cup units, a very stable foundation for mounting shock-absorbing arms or other gear is established.