Identify Part
Hello, thanks for posting! It looks like you could have either our S380-26 or S385-26 with the 2540 stamp option. The difference between the Series 380 and the Series 385 lies in the depth of the shoe. Take a look at the picture below for more detail. Once you have determined this dimension you should be able to select the appropriate balance.
We don't recommend going up on the stamp option. The stamp indicates the spring strength, which is calibrated to offset the weight of your particular window. Going up or down on the spring strength can make the window, respectively, difficult to open or unable to remain open. I apologize for this inconvenience. I recommend signing up for our auto-notification service, which will provide you with an e-mail when this part is back in stock.
