This unique "socket" type fitting automatically locks onto the mast toggle pin with a quick and easy push. The release is just as quick with a press of the lever (fits Forespar® mast toggle pins only). For Pole Dia. 3.5", Tube I.D. 3.260", Weight 1lb. 7oz. Made of Forespar's "Ultra" composite for light weight and resistance to corrosion.