Existing Part #: 26-3 JM5 CMC 8

Hey there, thanks for reaching out! It looks like you have either the S380-27 with a 1" shoe or the S385-27 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 2630 stamp for a sash weighing 13 to 19lbs.

Comparison of the S378, S380 and S385 balance shoes.