Inner hexagonal semicircle head-Screw series-老街-腾龙娱乐公司15559858555客服经理电话微信1-老街-腾龙娱乐公司15559858555客服经理电话微信2

Screw series

Inner hexagonal semicircle head

The internal hexagonal semi-circular head screw has larger tightening force and is made of alloy steel.