1937-1954 Dodge/Plymouth distributor

there are a couple model...series if you will..IGS; IAT while they will interchange in the engine...23 inch blocks US made...your tune up parts will be series specific..whatever model you should be able to locate and purchase, do order your tune up parts by the series that is marked on the red tag..if different than your application do record this somewhere for future reference....later models will have a green tag if for 12 volt operation...their timing curve may be a bit more than you want however due to the increase in CR and cam specs at the end of the flathead series. If you tell me your actual engine year application (see stamp on engine block above the generator, will be a letter + the next two numbers) I may be able to tell you what exact model you are needing example: IAT4011