Anti climbing device is an important railway accessory, mainly used to resist rail crawling and ensure the safety and stability of railway transportation. It consists of a rail clamp with a baffle and a threading pin. By clamping one side of the rail clamp onto the bottom of the rail and wedging the other side into the threading pin, the entire anti climbing device firmly grips the bottom of the rail, thereby preventing the rail from crawling. The installation of anti climbing devices not only directly improves the safety of railway transportation, but also reduces maintenance costs and has certain economic benefits.