Turbo Oil Pan drain return plug adapter bung fitting no weld Bolt on Turbo Oil Pan Return Plug. ALL NA to Turbo Conversion Projects Require to drill a Hole on the Oil Pan and weld a plug/fitting for Turbo oil Drain. This Plug is Bolt on, does not need to weld. Only needs to drill a hole on the oil pan, use the bolt to tie and seal it. Fits 5/8" Oil Return hose