Replaces OEM# 3873 and 3109

The outside diameter (OD) of these exhausts is 1

• Operation: The plunger extends approximately 1/2" at around 30psi to indicate sufficient oil pressure

These can be used with either short or tall risers and come with a knurled clamping area

These will keep you and your passenger from accidentally burning your leg while riding

Complete Motor Gasket Kit - Sportster 900cc 1957 - 1971 Shape_Custom Replaces OEM# 3873 and 3109Complete Motor Gasket Kit with coated head gaskets. Fits 1957 1971 Harley Davidson 900cc Sportsters. James Gaskets are known world wide for their close attention to quality and fit. Made in the USA.