Adjustable steel housing with non-ball bearing plastic roller
Used on Cox 21 and 22 series mirror door systems. Bi-Pass Sliding doors
Part may be stamped with numbers 21-717, 21-767, 21-718.

Color: Mill
Diameter: 1-1/2-inch
Height: 2-7/16-inch
Material: Plastic
Mount: Bottom
Roller Edge Type: Concave
Type: Concave
There is another roller that is convexed ( protrudes)

Related Mirror Closet Door Hardware:
25120 - Top Guide
25140 - Bottom with Convave Roller
25165 - Bottom with Convex / Protruding Roller

Priced and sold each.