Truth 45251 Traditional 7-1/2" Straight Arm Operator, LH Color:White It is a surface mount

It is a surface mount unit originally used by window manufacturers including Bilt Best

Truth #45275 (housing)

S-1081-71 on Short 4-7/8" Link

and Yale®)

Double-check handedness and stamped part numbers to prevent ordering errors

Truth 45251 Traditional 7-1/2" Straight Arm Operator, LH Color:White It is a surface mountTruth Traditional 7 1 2" Straight Offset Arm Casement Operator, Stainless Steel Roller, Left Hand This is a Truth Traditional style single arm casement window operator with a 7 1 2" (190. 5mm) straight, offset up arm. It opens and closes casement windows using a rotating gear housing paired with a fixed sash bracket and track. The arm ends in a 9 16" (14. 3mm) stainless steel roller button that rides in the sash track. Arm length is measured from the