30" x 1/2" channel guides

Hello!

With this combination of attachments, you could have either an S380-30 or S385-30 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. For the balance stamped "29 6", you'll need a 2960 spring strength option. As for the "2990" stamp, this is outdated and doesn't match any of our standard options so you'll need to weigh your sash on a scale to determine the appropriate spring strength option. There's a chart on the S380-30 and S385-30's store pages that will show you which option you'll need based on the weight of your sash.

And yes! We always suggest replacing both balances at the same time.

Let me know if you have any questions! 

Comparison of the S378, S380 and S385 balance shoes.