Pan head machine screw

The cross recessed pan head screw is a kind of strengthening and improvement of the cross slot. The usual method is to add a slotted groove through the screw head in the notch in one direction at the top of the cross slot. The screw can be installed with high torque through a special screw in tool or slotted screwdriver, and can also meet the needs of fast-paced production in practical work. However, the production process is more complex than that of cross groove and straight groove, and there is no very clear standard.