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This Sliding Patio Door Roller has two 1-1/4 inch (31.8 millimeter) diameter
Steel ball bearing rollers.
The steel housing assembly is 11/16 inches (17.5 millimeters) wide and 1 inch (25.4 millimeters) tall.
This unit is used by Keller and other door manufacturers.
There is another roller with a 1-5/16 tall housing that looks like this one.

Diameter: 1-1/4-inch
Housing Tab Style: Plain Back
Housing Width: 11/16-inch
Material: Steel
Roller Diameter: 1-1/4-inch
Roller Edge Type: Concave
Roller Material: Steel
Type: Concave
Width: 11/16-inch

Related items:
13261 - Keller 1 inch tall housing
13262 - Phillips 870 Marquee with 1-5/16 tall housing