Improved L-shaped bracket member of a pair of oppositely disposed back-to-back mirror image bracket members configuring when mounted, an improved replacement link chain for repair of a disconnected chain link drive mechanism, including a base flange mountable by bolt fastener to a substrate member carrying the chain link mechanism, and a perpendicularly depending side flange being of generally flat thickness dimension to define improved uniform gap opening between a pair of oppositely mounted side flanges of the pair of bracket members, and having an aperture extending through the thickness dimension of the side flange positioned with the aperture opening thereof disposed in at least tangential interference with the rotational radius of the bolt fastener to enable the rotating bolt to extend into the aperture opening to remove striking of the bolt with the adjacently disposed side flange when mounting or dismounting the base flange of the improved bracket member.