S385 channel balance?

Thanks for posting. This looks like it's either a S380-30 or S385-30. The only difference between these two Series is the 'depth' of the bottom nylon shoe. With the Series 380 the depth of this nylon shoe is 1", whereas with the Series 385 it is 1-3/32". Compare with your own and see what is best.

Once you know which balance to select, you will need to choose a stamp option. However, your stamp number of 29 9 is from an older rating system that we no longer use. To know what stamp option to select, you should weigh your window sash. You can then match that precise weight with one of the weight ranges listed alongside each stamp option on the product page. Let us know if you have any questions, or if your window sash falls out outside of these weight ranges.