Lock Nuts - UNF

Sometimes written as lock nuts, they also go by various other names, including half nuts, jam nuts and thin nuts.

Locknuts are used to lock a full nut in position to prevent it from working loose as a result of vibration or other factors.

Locknuts are often mixed up with Nyloc nuts, which are different. Nyloc nuts are self-locking nuts that feature a nylon collar in the top portion of the nut that locks the nut in place.

About UNF Thread

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.