non tilt counter balance replacement part number

Question

The string broke inside the balance :(

21 metal length, winged front and back, 1/2 wide metal, not sure if its a 380 or 385 and I think it's a 2030 option maybe?

stamped (20 3 DN Caldwell)

this is an original windows from my 1994 house.

Bob · Accepted Answer

The difference between the S385-21 or S380-21 is the depth of the bottom nylon shoe. The Series 385 has a depth slightly greater than 1". See the image below. It looks like you might have the S385-21, but please check the measurements to be certain. For a stamp option choose 2030.

Comparison of the S378, S380 and S385 balance shoes.