Replacement coil balance both left and right.

Thanks for posting. This looks like a 15-177 Pivot Shoe, which works with Series 152 Coil Balance springs. For a 10 pound sash, use the S152-5 5 pound springs, one for each side. You can reuse your old coil covers if they are not broken. Otherwise, see the 15-143, 15-144 and 15-145. These parts 'sandwich' around each individual coil. Let us know if you have further questions.