Window balance

Thanks for posting. This looks like a Series 140 Coil Balance assembly. To know what spring weight to select, measure the weight of the window sash these coil springs support, and then divide that weight in half. For the pivot bars, this system often uses either the 26-398 or 26-405, but you'll need to remove an old pivot bar and compare to these options to see if either match what you need. Let me know if you have further questions about any of these items.