Hex Set Screws - UNF - YBZP

Hexagon set screws, or hex sets to give them their common name, are available in both metric and imperial thread sizes in a wide range of finishes. A set screw differs from a bolt in that the shank is threaded all the way from the tip to the head.

UNF stands for Unified National Fine. It is a common imperial thread type with more threads per axial distance than its UNC equivalent.

Unified thread types (UNF and UNC) were introduced at the beginning of World War 2 to enable the interchangeability of machinery manufacturing between the USA, Canada and Great Britain. Still commonly found on a vast array of old machines and vehicles in the UK, UNF and UNC threads continue to be the standard thread in the USA and Canada.

A YBZP or yellow bright zinc plated fastener is one which has a thin coating of yellow coloured zinc added during production. This protective coating adds durability by protecting the product against rust or oxidisation.