bought a mystery 850 double pumper...
the first pic is good the second pic is the outside of the booster, you need to measure the smallest part of the bore, the venturi. It's hard to measure but if you have one of these its very accurate.
the first pic is good the second pic is the outside of the booster, you need to measure the smallest part of the bore, the venturi. It's hard to measure but if you have one of these its very accurate.