channel balance mark 28c

Hello,

With this combination of attachments, you could have either the 29" long S378, S380, or S385 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. 

Your 28C stamp would correspond to 2830 spring strength options for your replacement balances, which will support a sash between 16 and 23 pounds. Thank you and let us know if you have any other questions or concerns.

Comparison of the S378, S380 and S385 balance shoes.