Finding the correct channel bracket

Thanks for reaching out! The parts you are searching for are referred to as channel balances. They help to support the weight of the sash when opening the window.

Your channel balances look like they could be either the S380-29 with a 1" shoe or the S385-29 with a 1-3/32" shoe.To determine which series is needed for your window, look over the dimensions from the diagram below to confirm the depth of your bottom shoe. Let me know if it does not match either measurement.

You'll need to select the 2820 stamp.

Comparison of the S378, S380 and S385 balance shoes.