Looking for Window 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. 

To further review, are you able to confirm the length of the metal channel excluding the nylon attachments? 

Comparison of the S378, S380 and S385 balance shoes.

Thank you,

Based on the 29C stamp, the length of the metal channel excluding the nylon attachments should measure 30" please compare. 

If so, you should be able to use a 2930 stamp option that can support a 16 to 23 pound window sash. We recommend weighing the sash to confirm it falls into this range.

Please let me know if you have any additional questions!