not sure what you want ,but straight from the ORD 9 G-749 catalog,Bolt: with vent hole 1/2 20 UNF-2 x 1 15/16 (filler pipe), item #2 ,FITTING : cop - alloy,5/8 dia bolt hole at top,7/16-24NF-2 female pipe thread at side connection,(filler pipe cap ), hope this helps,good luck on your project