flat spring window lift

Hello, thank you for posting, 

Please start by reviewing the style and dimensions of the 15-192 Certainteed pivot shoe to see how it compares to your original. Please note that past customers reported that they needed to shave down the "nubs" on the face of the new shoe to fit into the track. This pivot shoe is compatible with the S170 and S171 coil springs. 

detail of 15-192

If you have a single coil assembly, take a look at the S170-406 based on the original stamp. This spring alone can hold 6 pounds of weight. One on each side can support a 12 pound window sash, please compare.