Not sure if it's been used as have several in a creat listing is for one
Exhaust Pipe, BSA M20, M21, Rigid, 1938 WD Models - Made in England
BSA M20 RIGID REAR WHEEL BEARING THRUST WASHER NOS GENUINE BSA
BSA M20 Rigid oil tank with cap classic bike
BSA M20, M21, M33, B31, B33 Plunger Rear Brake Drum and Sprocket 42T 65-6294
BSA M20/21 B31/33 KICKSTART RATCHET PINION (66-3080) PLUNGER/RIGID - UK SUPPLIED