This tandem wheel roller assembly is constructed of a pair of steel wheels and an adjustable steel housing. Each wheel has a concaved (center grooved) edge and features a steel inner race, steel ball bearings and a 5/16 in. roller width. The outside diameter of these rollers is 1-1/4 in. and they are used to replace damaged patio door roller assemblies in sliding glass doors. These tandem roller assemblies are used by a variety of patio door manufacturers.