Accelerator pump diaphragms for Solex Paita carburetors. .016" thick. Applications typical to 50s era Mercedes and others. You have to swap over your metal components from the old diaphragms. These are the result of a lot of research into the correct materials and the sourcing of these materials also the fabrication of the die itself. The material is difficult to purchase in less than full roll quantities and is very expensive. These tend to be only available when buying complete kits. Some kits don't include these. You may notice that there appears to be a hole missing as compared to the originals. That is because that hole is not used. I have several of the paita carbs and the hole is not there. I will add more photos to demonstrate this. I am telling you all of this so you don't think that these are incorrect because of the missing hole. I am also working on the die that makes the gasket used on the same pump. I hope to have that die complete in about a month. The pump housing is not included, it is for reference. These may fit other Solex carbs. The hole spacing on the 4 main mounting holes is 1.375 x 1.375. If you know of other obsolete or hard to find items for these cars I would like to hear from you. So, for $6 each and free shipping how could you possibly go wrong? You should buy just to have them on hand.