11-17-001 Fits 250cc square barrel cylinders up to 1977, also fits 350-360cc up to 1974.
29-17-001 Fits 360-370cc Pursang, Frontera & Astro models from 1975 on 
1T164-17-001 Fits 250cc Pursang, Frontera & Astro models from 1978 on, also fits 1976 and newer 350cc Alpina and Sherpa T models