Window Spring

Thanks for writing in. See either our S380-30 or S385-30, as well as either our S380-36 or S385-36. The only difference between the Series 380 and Series 385 is the 'depth' of the bottom nylon shoe, so compare both with your old hardware to see what matches best. For the 30" long balances, you will need a stamp option of 2940; for the 36" long balances, you will need a stamp option of 3540. Let us know if you have any other questions.