Hello,
With this combination of attachments, you could have either the S380-24 or S385-24 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.
Since your stamp code differs from our balance strength options, you'll also need to weigh your sash to determine which option you'll need. There is a chart on the product page that explains how to choose your option based on the sash weight. Thank you and let us know if you have any other questions or concerns.
