I've been dealing with vintage motorcycles for over 35 years and I've never been able to figure out what this is from. If someone knows what it fits please let me know so that it is more likely to end up with someone that can use it. (Use "ask seller a question " to send a comment)  Looks almost unused.  Could be from AJS  Ariel BSA Triumph Panther Norton Enfield Vincent Velocette Rudge Brough Superior Munch BMW DKW MZ NSU Harley Henderson Indian Pope Crocker ACE Excelsior Zundapp Matchless Guzzi MV Honda Yamaha Kawasaki Puch Jawa Husqvarna