need window's balance

It looks like you may need our S395-30 channel balance. As long as you make sure that you're only measuring the metal channel and not including the nylon attachments in your measurements, you should be good to go. Based on your pictures, it looks like the stamp on your channel might say 29 3, which might be a 2930 option.

Make sure to check your stamp to be sure that you're getting the correct spring strength. If you're still unsure, I'd recommend removing and weighing your sash. There is a chart on our product page that will tell you which option to choose based on your sash weight. 

Let us know if you have any more questions. Thank you!

Hey! I just noticed this discussion, and I'm not so sure about the order you placed. "2930" was just a guess, but it turns out that's probably not right. If you have "2919," then you need to weigh the window sash to get the proper option from the chart on the S395-30 webpage. I've held your order to prevent it from shipping wrong. Please weigh the sash and call our customer service center to handle this order! The phone number can be found by clicking this word: here.

Thanks for getting back to us! Look at our 18-185 top sash guide and compare this to yours. This looks like a good match to me.