Window balance 37in. 3640 winged foot

Thanks for your post! Your window balance can be replaced with the S378-37, S380-37, or the S385-37. You'll need to measure the depth of your shoe to confirm the right series.

I'm not able to cross-reference the 3635 stamp on your balance, so I cannot confirm if the 3640 stamp option is the correct replacement. You'll need to weight the window sash to confirm that it is between 23 to 30lbs.

Comparison of the S378, S380 and S385 balance shoes.