This article shows the different types of operators used on A-Series and 400 Series casement windows. It includes images of each type and information on replacement operators.

Types of Operators Used on A-Series and 400 Series Casement Windows

Depending on the vintage and size of an A-Series or 400 Series casement window, it will use either a split-arm operator or a straight-arm operator. To identify the type of operator used on your casement window, open your window and examine the upper arm that extends from the operator handle. Then, compare the operator on your window to the images below.

Use the images below as a reference for how each casement window operator appears when viewed from the interior of the home. 

Split-Arm Casement Window Operator

Split-arm operators have a folding arm that attaches to a sash bracket located in the corner of the window sash. For more information on replacement operators, see Split-Arm Operators for A-Series and 400 Series Casement Windows.

Split-Arm Operator

Split-Arm Operator Parts

Straight-Arm Casement Window Operator

Straight-arm operators have an operator arm that slides along a channel located along the interior bottom of the window sash. For more information on replacement operators, see Straight-Arm Operators for A-Series and 400 Series Casement Windows.

Right Hand Straight Arm Operator

Straight Arm Operator Parts

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