Channel Balance Replacement

Thanks for posting. Yes, it sounds like you need new channel balances. Is the metal channel, not including the nylon attachments on both ends, 29" long? If so, this might be either an S380-29 or S385-29. The only difference between these two balances is the depth of the bottom nylon shoe, or the measurement from 'heel' to 'toe'. See the illustration below for reference. Compare both with your old hardware to see what matches best.

Comparison of the S380 and S385 balance shoes.

You then have to choose a stamp option, which denotes the strength of the balance. Your old balance's stamp of 28F might conform to our stamp option of 2860, which designates a balance that can support a window in the weight range of 32 through 35 pounds. I advise weighing the window sash that these balances support just to confirm it falls in that range. Let me know if you have further questions.

That sounds like a plan. If you determine that you need the S385 balances, our full return policy can be found here. Just let us know if you have any other questions.