Our circular surgical stapler insurance mechanism should be flexible to open and close and safe to use. The return spring should be flexible enough to return quickly when the handle is released. The stapler should have good anastomosis and cutting performance, and the staple end is sharp. After anastomosis, the staples are “B” shaped, and the circular knife has almost no curling edges or chipping edges. After the anastomosis, the anastomosis can withstand a pressure of not less than 3.6 × 103Pa, and there is no leakage or tearing.