Many of our calls are from homeowners looking to fix there so and so brand casement windows. Weathershield is one of those brands that we run into. Weathershield Casement Windows usually use Truth Window Hardware, and more specifically, we usual see the Truth Split Arm Operator 30905. The best way to determine which operator you have is look at the arms that attach the window operator to the window. With these numbers you can enter them into the “search entire store here” on our website, Residential and Commercial Window Parts. The numbers that are the most help are the 5 digit numbers that start with a 2 or 3.