Item marked 1630 BSI or 1

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. 

The length of the metal channel excluding the nylon attachments should measure 17" long and you will need a 1630 stamp. Please review and let us know if you have any additional questions. 

Comparison of the S378, S380 and S385 balance shoes.