This is a steel tandem C-tab roller assembly with 1-1/8 inch steel ball bearing rollers. The C-tab fits around the corner screw and captured by the side stile and bottom rail as they are drawn together. The adjustable stamped steel housing is 11/16 inch wide with a flare width of 13/16 inch, 1-1/16 inch tall and 3-1/8 inch long. Used by Pacific, Elco and a variety of other sliding patio door manufacturers.
Sliding Glass Door Tandem Roller Assembly with 1-1/8" Steel Ball Bearing Roller - Fits Elco™ Doors and Others