Bolt and #nut are a type of fastener typically made of metal, and characterized by a helical ridge known as a thread
Nut is a metal piece with a threaded hole that can mesh with bolt
Bolt diameter is designed as the needed duty on #tensile and #shear and threads are designed on shear and #stress then knowing needed threads to handle the weight
Bolt’s head is made with many shapes to be catched with wrenches .. and the nut typically has the same shape .
