This is a white plastic roller assembly.
Used by Elco, and Better-Bilt aluminum sliding windowsFlat edge design3/8 in. Brass Flat-Edge Roller Assemblies (2-pack) The roller is made of brass flat edge and most often used by Elco, Better- Bilt Aluminum and a variety of other manufacturers. rollerWhite plastic design with brass roller2-packInstall 2 per windowA slotted head screwdriver is required for replacementFor further dimensional information, please see the line drawing.3/8 in.