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1-1/4 inch steel ball bearing roller 
Adjustable steel housing assembly 
Used by several glass door manufacturers 
Housing dimensions: thickness, 9/16 inch; length, 1-5/16 inch; height, 1-1/8 inch; overall thickness, 21/32 inch. 

Diameter: 1-1/4-inch 
Housing Tab Style: F-Tab 
Housing Width: 9/16-inch 
Material: Steel 
Roller Diameter: 1-1/4-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