Used also on Closet Doors.
1-1/4 inch steel ball bearing roller
Adjustable steel housing assembly
Used by several glass door manufacturers
Housing dimensions: thickness,5/8 inch; length,1-27/32 inch; height,1-1/4 inch; overall thickness, 13/16 inch.

Diameter: 1-1/4-inch
Housing Tab Style: F-Tab
Housing Width: 5/8-inch
Material: Steel
Roller Diameter: 1-1/4-inch
Roller Edge Type: Concave
Roller Material: Steel
Roller Width: 5/16-inch
Type: Concave
Width: 5/8-inch

Sold each, priced each

Helpful Article: How to Replace Rollers in an Aluminum Sliding Glass Door