This Fruitland F130 Coupling insert (Sleeve Insert or element) is made from durable Buna material offering dependability, quiet performance, this is a low maintenance sleeve coupling insert and easy to install. This flex insert absorbs shock, slight misalignment and end float. Use sleeve insert with Fruitland F130 coupling components. This insert fits F130 couplings commonly found on vacuum trailers and vacuum trucks. The outside diameter is 5″.