29 inches 28B channel balance

Hello, thank you for posting! 

With this combination of attachments, you could have either an 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. You will need a 29" balance with a 2820 stamp option, meaning your window sash weighs between 12-16 pounds. 

Comparison of the S378, S380 and S385 balance shoes.