Emily from SWISCO responded:
November 2, 2021
Hi, Marc. With this combination of attachments, you could have either an S380-29 or S385-29 channel balance. You’ll need to measure as shown below. The Series 380 has a 1" bottom attachment, and the Series 385 has a 1-3/32" attachment. We also suggest weighing your sash on a scale to determine the appropriate spring strength option. There's a chart on the S380 and S385's store pages that will tell you which option you'll need based on the weight of your sash. If you have any questions just let us know! Comparison of the S380 and S385 balance shoes.
|