Triumph petrol tank rear attachment double spigot rubber washers (each). Double shouldered washers / buffer with 5/16 inch hole. Used on 500 & 650 unit construction from 1964 (not Oil in frame models). OD 1in, ID 5/16in, Ht 3/4in, Step1 1/8in. Step2 3/16in Centre Ht 7/16in Original Part Numbers: F5336; 82-5336; 82-5336 - double spigot rubber