1790 27 Channel balance

Hello there. Please double-check the channel length. Do not include the nylon fittings on both ends in the measurement. I believe it should come out to 18". If so, this is an S395-18. You will need to choose a stamp option, which designates the strength of the balance. Your old balance's stamp of 1790 is from a rating system not in use. To know what stamp to select, obtain the exact weight of the window sash these balances support. You can then match that exact weight with one of the weight ranges listed alongside each stamp option under the S395-18 product description. Let me know if you have further questions. 

No, for a 30 pound sash the 1750 option would be too weak. Your window would likely drift close by itself after you open it. We don't currently carry a stamp option for an 18" long balance that can carry 30 pounds, but please give us a little time to look into it. 

I'd also recommend that you triple check the sash weight just to be safe. Please make sure to get it down to the ounce; there is a chance we have to get this specially calibrated for you, so precision will be necessary here. 

Reviewing your old stamp again, I see the number "27" printed after the code. That may in fact represent the exact weight of your sash.

Thanks! That's a huge help. 432 ounces equals 27 pounds exactly, which also matches the code on your stamp. That means we can use the 1770 stamp option; two balances with this stamp can carry 23 through 29 pounds, which should be perfectly suitable for your sash.

What I'll do now is email you a purchase link and price quote that will let you add two of these assemblies to your cart. You may then checkout as normal. At this stage, I recommend that you double check the configuration of the Series 395 to ensure that everything other than the strength matches and is good to go.

Please let me know if you had any other questions and I would be happy to assist you.