This listing is for a pair of 3mm thickness Cork petrol/oil cap gaskets - to fit Douglas 1912 models where the oil filler was smaller than the petrol filler cap - as shown in the accompanyning photographs. Price is per pair of gaskets
As can be seen from the accompanyning photographs - these gaskets are made from best quality 3mm cork gasket material, with a breather hole pre-punched in the petrol cap, in the position that matches with the hole on original petrol caps. This type of 1.875" screw on thread - with a knurl at the top of the cap were fitted to most Douglas flat tank models for the petrol filler - but after 1912 the period Douglas Spare Parts catalog shows that the oil filler was increased in diameter to the same size as the petrol filler - so if you have a model around 1913-14 you might want to double check which size oil filler cap you have - we do sell a pair of the larger size as well - Item 0984