Socket Screws - Countersunk - BSF

BSF (British Standard Fine) is an imperial thread Introduced as a fine-pitch alternative to BSW and commonly used in engineering and automotive applications in the UK.  It was superseded by the UNF thread type in the 1940’s.

A countersunk head is usually used when no part of the fastener head is required to be protruding above the level of the substrate. Countersunk heads can also be recessed and filled over if a hidden fixing is required. Usually abbreviated to CSK.