S&S Socket head plug, 1/4" NPT

Socket head plugs for blocking of oil or vent holes when changing the lubrication or venting system. For example when changing from chain to belt primary on a pre 1984 Big Twin, you must block of the front chain oiling system. This can be done by removing the fitting and installing the 1/16" NPT plug. 1/4" NPT and 1/8" NPT plugs are used to block vent holes on crankcases etc.