Bushing for cover on Fairbanks-Morse FM J series magnetos with a two-piece cap found on many Allis-Chalmers tractors. Replaces Fairbanks Morse part number B5950A. Please note: If you purchase a new cover (GR1261), the bushing is already installed. You would purchase this bushing if you are going to re-use your existing cap and need to replace only the bushing.