British motorcycle thread repair kit. Size OBA which was used to repair small threads on British motorcycles 1930-1970's. If you are not familiar with OBA size then goggle it on the computer. Used on all makes of British motorcycles from the periods. Also used on British cars. A must for British restorers of small components. Only used once. Complete with taper, medium and bottom taps plus threaded wire inserts. These are like US Helicoils. Clean up damaged threads, fabricate replacement parts, repair stripped threads. Study the photos and ask questions if any. $50 or Best Offer. If the ad is up then the inserts are still for sale. I have finished all of the antique motorcycles that I will restore. It is now up to the next generation of British m/c restorers. Cheers and be safe. David in Sunnyvale.