Window balance

Thanks for posting. This looks like a 15-177 Pivot Shoe, which works with Series 152 Coil Balance springs sold separately. There are two springs attached to this shoe. For any spring stamped '7', you can use the S152-7 7 pound spring. Be sure to check the stamps on both springs before proceeding, so you select the correct stamp weights for both replacement springs. If your old coil housing is undamaged you can reuse it--otherwise, see the 15-143, 15-144 and 15-145. These newer style parts 'sandwich' around each individual spring. Let me know if you have further questions.