Square type of shank of set bolts used in the machinery equipment industry.We specialized in manufacturing hardware, such as standard and special screw, nut, spring,bolts ,machining parts etc.Most fasteners'orders ship in 30days,some of the most screw ,bolts ,nuts,are standard,and also can be customized with your drawings and sample.To see more of other products available on standard and non standard fasteners,check out our web kinsomhardware.com.