Description :
No. 1 is for special design on head of screw or bolt. This is relate to tool for tightening and loose. In example Phillips is cross on head and use with screw driver for tightening.
No. 2 is for shape of head. Flat/socket/Oval/Pan/Truss/Round/Button/Head/etc. This is relate to requirement for each equipment
No. 3 is for shape on bolt. Bolt is a flat shape, Screw have a thread, wooden screw is special thread. In case we need bolt with screw it’s mean that flat shape and screw in one bolt, user should be advise how long of thread that the need.
Finally, one order name should specific at least 2 detail for shape of head and shape of bolt.
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