Can You ID this Channel Balance
I need 4 of the 25 inchers
This looks like a Series 390 Channel Balance; look over the nylon fittings to confirm. Measure the metal channel, not including those nylon fittings at either end, to confirm the lengths you need. You'll then need to choose a stamp option. Look for a stamp code on the metal channel. If there is none or you are uncertain, obtain the exact weight of your window sash. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on every balance's shop page.
stamp is 2810. measures 29" metal to metal. need 10
stamp is 2420. measures 25" metal to metal. need 6
series 390? could not confirm so I send close up of nylon fittings in hopes you can identify. Home built 1978
Matt