Thread Series Designations - British Screw Threads

STD. TAP & DIE MARK. PROD. THD. DESIGNATION THREAD SERIES REFERENCE BRITISH STANDARD
BA BA British Association BS93
BSC BSC British cycle BS811
BSF BSF British WHITWORTH Fine BS84
BSW BSW British WHITWORTH Coarse BS84
OBSOLETE BSPP British Straight Pipe OBSOLETE
OBSOLETE BSPT British Taper Pipe OBLOSETE
WHIT WHIT British WHITWORTH Special BS84
STD. TAP MARKING*   BRITISH PIPE THREADS  
G 1/4 Rc 1/4 Rp 1/4 G Rc Rp British Internal Straight Pipe for Mechanical Joints British Internal Taper Pipe for Pressure Tight Joints British Internal Straight Pipe for Pressure Tight Joints BS2779 BS21 BS21