Tilt window

Hello, thank you for posting! 

Your pivot shoe resembles the 15-177 that is compatible with the Series 152 coil springs. Please compare the dimensions below. The 7K should indicate that each individual coil can hold 7 pounds. To confirm, if you have 2 coils on either side of the window, your window sash should weigh 28 pounds. Please let me know if you have any questions.