Window Balance Replacement

Home Owner from California

May 23, 2026 2:19 pm

I need to replace several window balances for two different sized windows.
The sticker on the windows are labeled
SERIES: 6210/6230/6230J/6270
H-R25-48x78
H-R30-48x96

The larger window balance is stamped 34 4 JV CMC 7
The smaller window balance is stamped 20 2 IV CMC 7

4 user uploaded images

5 Replies

Bob from SWISCO

May 25, 2026 2:09 am

Hello there. I am afraid there's no way of narrowing down what you need from this information. Please remove the balances and send us clear photos of the nylon attachments on both ends. We'll be able to narrow it down from there. See the videos on this page for more information.

Home Owner from California

Jun 1, 2026 5:34 pm

Okay, thanks. The photos on the brown couch are for the larger balance, while the ones that are still in the window frame are for the smaller one.

5 user uploaded images

Home Owner from California

Jun 1, 2026 5:37 pm

The smaller balance is 21 inches long, and the larger is 33 inches.

Bob from SWISCO

Today 4:15 pm

Thanks for getting back to me. If the metal channels (not including the end attachments) are 21" long and 33" long respectively, it looks like you need either the S378-21, S380-21, or S385-21, and then either the S378-33, S380-33, or S385-33. The only difference between the Series 378, Series 380 and Series 385 is the 'depth' of the bottom nylon shoe. See below.

Comparison of the S378, S380 and S385 balance shoes.

You then have to choose a stamp option, which reflects the balance's strength. For the 21" balances choose 2020; for the 33" balances, 3240. Let us know if you have questions.