13 9 22# BN CALDWELL spring balancer

To begin, it's important to know that there are three variables controlling which balance you need: the length, the strength, and the Series of the balance.

Measuring the metal channel (as you did) yields the length, which is 14", in your case.

The strength depends on the weight of the window sash that the balance must lift. Remove the glass/frame portion of your window and put it on a scale. There is a chart on the item webpage that will tell you which strength option to choose, based on the weight.

As for the Series, we determine it based on the plastic attachments. For two winged attachments, we need to determine if you've got a Series 380 or a Series 385. To do this, measure the bottom shoe, as shown in the photo below. A 1-3/32" shoe indicates the S385-14, but for a 1" balance, you need the S380-14.

Aha, I see. I think the S385-14 is the way to go. Since the sash is 18.8 pounds, though, it will have to be custom made with a stronger spring. Can you just tell me how many you need? Once I know that, I can email you a custom balance order link and price quote.