Retractable faces limit position and prevents guardrail bar

The utility model belongs to the technical field of the construction, concretely relates to retractable faces limit position and prevents guardrail bar. Should prevent that guardrail bar included sleeve pipe no. 1, sleeve pipe no. 2, fixing bolt, the U -shaped mounting, the internal diameter of sleeve pipe no. 1 is greater than sleeve pipe no. 2, be equipped with the rectangle opening on the sleeve pipe lateral wall, be equipped with a plurality of bolt holes on two lateral walls of sleeve pipe, respectively there is a bolt insertion hole on two extension edge suitable for reading of U -shaped mounting, sleeve pipe no. 2 is inserted and is located in the sleeve pipe no. 1, the bolt hole corresponds with the rectangle opening, penetrate behind the bolt hole in inserting the middle jack of locating two U -shaped mountings behind sleeve pipe no. 1 and two fixed connection of sleeve pipe through fixing bolt. Fixing bolts, easy operation, practicality are strong, and constructor is glad to be used, save the link o