Window channel bar

Hello there. This looks like it might be the S380-30 or S385-30 Channel Balance, depending on the shoe depth. See below. You also have to choose a stamp option, which reflects the balance's strength. Your old stamp of 29-9 is from a rating system we do not use. To know what to pick, weigh the window sash these balances support. You can use that exact weight to choose the right stamp option.

Comparison of the S378, S380 and S385 balance shoes.