SIZES: 1/8GAS fits AJS and Matchless
MEDIUM 1/4GAS (or BSP) (13,04mm) fits most makes, Norton, Triumph, Enfield, Velocette, Ariel and the last BSA’s
LARGE 3/8GAS fits BSA’s pre 1971
We also sell taps and dies in GAS/BSP sizes.
NUGGET OF WISDOM: Don't play with petrol taps. Only use taps when wet. Keep the corks soaked in fuel or they will shrink. Most taps die on the way home in the car.