Identifying channel balance

Thanks for posting. I see the bottom fitting, or shoe, has wings, or those side tabs. Does the top fitting have them as well? I can't tell from these photos. Please confirm. From there we should be able to narrow down the identity. 

The stamp 32-9 is from an obsolete rating system. The other stamp of 32-4 conforms to our stamp option of 3240, which designates a balance that can support a window sash in the weight range of 23 through 28 pounds. It's indeed a little odd to have two differently stamped balances in the same window, so to be safe I'd weigh the sash to confirm it falls within that range. Let me know what you find. 

Hey Grant. Sorry, I should have clarified: the stamp option, while very important, only tells us the strength of the balance. Not its identity. The identity is determined solely by those fittings on both ends, hence why I needed photos of them. Thank you for providing those. You have either an S380-33 or S385-33 Channel Balance. The difference between these two balances is the depth of the bottom nylons hoe, or the 'heel-to-toe' measurement. Compare both with your old hardware to see what matches best. Use the illustration below for reference.

Comparison of the S380 and S385 balance shoes.

Now regardless of whether or not you have the S380-33 or S385-33, you have to choose a stamp option, which again, tells us the balance's strength. This is where you might go with 3240--but again, because your window oddly had two different stamped balances, I'd highly advise making sure your sash falls within the weight range that 3240 can support, which is 23 through 28 pounds. If that's the case, then go with 3240. Let me know if that all makes sense, or if you have further questions. 

Perfect! Sounds like a plan. If your sash is 40 pounds then the 3270 option should be perfect.

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