Polyurethane positioning bolts are used in the positioning part to buffer and protect the trolley assembly. The transverse design of the buffer bolts can resist greater impact force. reduce vibration. Using square neck bolt structure, only need to tighten the hexagon nut, can be locked with the Strut Channel, easy to install, convenient. made of high strength steel,high strength, impact resistance. Black powder coating, anti-rust treatment. The trolley limit is installed inside the Strut Channel, which is beautiful and will not affect the use of other products