1-1/2 inch Steel ball bearing roller
Adjustable steel housing assembly
Used by Arcadia, Northrop, and several glass door manufacturers
Held into bottom rail by tabs - 
To remove Push forward and hooks will disengage, pull out

Housing dimensions: thickness, 15/16 inch; length, 2-3/16 inch; height,1-5/16 inch.

Diameter: 1-1/2-inch
Housing Tab Style: Unique Housing
Housing Width: 15/16-inch
Material: Steel
Roller Diameter: 1-1/2-inch
Roller Edge Type: Concave
Roller Material: Steel
Roller Width: 5/16-inch
Type: Concave
Width: 15/16-inch
Sold each, priced each