Looking for replacement parts for windows coil

This Pivot Shoe looks like our 15-180, which uses the 15-181 Double Support Detent Clip. This coil balance system uses our Series 190 Coil Springs. Look for a stamp code on the spring that indicates what spring weight you need to select. If there is none or you are unsure, weigh your window sash. Give us that exact weight and we will work out what you need.

All pricing is listed right on each item's shop page. Let me know if you have further questions. 

If the sash weighs exactly 19.6 lbs, I would use (2) of the S190-540 5 lb springs on each side of the sash. This would equal 10 lbs of support on both sides, for a total of 20 lbs overall--this is close enough to the sash weight of 19.6 lbs.