Window guide replacement

I can't tell from your photos, but I believe the metal channel not including the nylon fittings on either end is 25" long. If so, see our S380-25 or S385-25. The only difference between these two channel balances is the depth of the bottom nylon shoe, or the 'heel-to-toe' measurement, so compare both with your old hardware to see which you need. You'll then need to choose a stamp option. Your old stamp of 24DS31 should indicate your window sash weighs 31 pounds. In that case, choose a new stamp option of 2465, which supports a window sash in the weight range of 30 through 33 pounds. Let me know if that sounds right, or if you have any further questions.