Window sash balance replacement

Question

I'd like to order 6 of these sash balances.
They're 20 in long, 9/16 (inside measurement) metal channels.

Tom · Accepted Answer

I'm thinking this is S385-20, if the shoe is 1-3/32" as shown below and the channel is 20" by itself. You can order the same "1930" weight option that your old balance used when you purchase the parts online.