*Now In Stock!* New English Made Triumph & BSA Twins CEI Clutch Securing Mainshaft Sleeved Nut. For a long time this part was considered “Hard To Find”! Not anymore! Made to complete O.E.M. Specs in England! Just install and off you go! Nut measures 9/16″ with a thread pitch of 20 TPI (CEI). Fits many Triumph Unit & Pre-Unit Twins 350, 500 & 650 (Bonneville, T120, Tiger, T110, T100, 3TA, Tiger, Etc) from 1953-1967. Also fits many BSA A50 & A65 Unit Twins (Lightning, Rocket, Wasp, Firebird Scrambler, Royal Star, Etc) from 1962-1972. Please refer to your parts catalog for proper fitment.*****Please note that this Nut will fit more Triumph models up to 1967 that are not listed abouve! Check your parts book and thread pitch!*****Made in EnglandO.E.M Part number is 57-1047, T-1047, 68-3030 or 68-3300