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Steel ball bearing roller
Adjustable steel housing assembly
Used by several patio door manufacturers.
5/8 inch Wide Housing

Diameter: 1-1/2-inch
Housing Tab Style: F-Tab
Housing Width: 9/16-inch
Material: Steel
Roller Diameter: 1-1/2-inch
Roller Edge Type: Concave
Roller Material: Steel
Roller Width: 5/16-inch
Type: Concave
Width: 9/16-inch

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