Coil Balance System ID

Thanks for posting. The pivot shoe in your photos looks like an older version of our 15-180 Coil Balance Shoe. This shoe uses our Series 190 Coil Springs. To know what spring weights you need, look for stamp codes on the spring tape. If there are none, or you are uncertain, obtain the exact weight of your window sash. Give us that precise weight, and we'll work out what you need.

Perfect. See our S190-840 Coil Spring. This supports 8 lbs of weight individually. If you had one on either side of the sash, that would equal 16 lbs of support. If you had two on either side of the sash, that would equal 32 lbs of support. Let us know if you have any other questions.