coil balance

Question

I have enclosed pics of all sides. The only mark is a m or 3 on back of balance shoe

Bob · Accepted Answer

This looks like our 15-180 Pivot Shoe, which uses our Series 190 Coil Balances along with a support clip like the 15-181. To know what spring weights you should select, give us the exact weight of your window sash, and we'll do the math to work it out for you.