TracTuff Radiator Cap Bung
TracTuff billet radiator cap bungs are designed for use with my 3" and 4" billet tank lids; they match perfectly to the lids ID for a simple inside weld that you cant see once finished. On occasion, I have used them for odd projects, as long as there is a 1-1/2" hole.
I also offer the same two cap bungs with a 1-1/4" counter bore for easy locating on a 1-1/4" OD tube... just select the counter-bore version.
NOTE: The import cap bung has a 1/16" NPT for connection to an overflow and uses early model Honda (88'-91' Civic/ CRX and 90'-93' Integra) cap. The domestic version has been discontinued.