UNF Imperial Machine Screws

UNF (Unified Fine) machine screws are widely used in precision engineering, automotive, aerospace, instrumentation and applications where a finer thread pitch is required. The fine thread form provides excellent resistance to vibration, improved tensile strength and more precise adjustment compared with UNC.

Typical uses include engine components, suspension systems, machinery assemblies, hydraulic fittings, instrumentation, and any application where a strong, fine-pitch imperial thread is essential. UNF screws are also common in American and international equipment, making them important for repair and maintenance work.

The Unified Thread Standard (UTS) was introduced in 1948 to harmonise imperial thread forms across the UK, USA and Canada. UNF threads use a 60° profile with a finer pitch than UNC, offering greater strength in hard materials and improved clamping performance. They remain widely used in engineering, automotive and aerospace industries.