1 59/64... Melling MPS 172 They come 25 to a box, or you get one with the frost plug kit, which is melling P/N MPE 119BR for the good brass plugs.. the front galley plugs and rear cam plugs are always steel. If you only need one, and no one local has it, PM me your address, I will mail you one, I have boxes of them.. JW