New English Made BSA Unit Twins Primary Chain Adjuster Tensioner Blade. For a very long time this part was considered “Hard-To-Hard”! Well, not anymore! Get Em’ while you can, stock is limited! Quality is just as good as O.E.M.! Fits all BSA A50 & A65 Unit Twins (Star Twin, Thunderbolt, Rocket, Lightning, Hornet, Wasp, Cyclone, Spitfire & Firebird) from 1962-1972. Please refer to your parts catalog for proper fitment.*****Please note that this part will only fit BSA Unit Twins as stated abouve!*****Made in the UKO.E.M Part number is 70-8310 or 68-0244