This CRL Sliding Glass Door Roller boasts a 5/8" (16 mm) wide and 1-3/16" (30 mm) tall steel housing. The nylon ball bearing roller is 1-1/4" (32 mm) in diameter and 5/16" (7.9 mm) wide. It is utilized by International and many other patio door manufacturers. Each package contains one roller assembly. This roller assembly is used by International Patio Doors.