B&P Lamp 3" X 12" Clear Slimline 12" Chimney Clear Slimline chimney slips inside ball shades with narrow openings, for #2 burners and 3 inch galleries 3 inch fitter 12 inch height 3 1/3 inch bulge All glass chimneys will vary in thickness due to the manufacturing process. They will fit the holder/burner specified in their description