Hurd Tiltin Sash window

Hello, Mark. Based on the design of the clip, I believe you need our Series 190 coil spring. You will need the stamp off the old one to confirm the best option, though. If no such stamp exists on any of your old coils then I will need to know the exact weight of your sash so that I can make a more precise recommendation.

Thanks, Mark. So, since you have four springs, you need to divide that weight evenly between them. I recommend using one four pound spring and one five pound spring on each side of the window; that'd be our S190-440 and S190-540, respectively.