Window balances

Question

The steel channel is 25 inches long and five days of an inch deep. One side of the window failed when the rivet holding the spring bent and pulled itself out of the holes which held it.  Of course I'm going to be replacing both sides of the window. As best I can tell my son and I installed Windows 25 years ago. I am impressed with your website and originally thought I'd use my best judgment in order the balances. However, your invitation to send photographs is the right thing to do. The white clip is 1 1/8 inch deep and I found the number 158 etched into the steel channel

Bob · Accepted Answer

Greetings, and thanks for reaching out. Is the metal channel 25" long, not including the nylon attachments at both ends? if so, this is likely either an S378-25, S380-25, or S385-25 Channel Balance, depending on the depth of the bottom nylon shoe, as shown below. If you're certain the shoe is more than 1" deep, then it's the S385-25.

Comparison of the S378, S380 and S385 balance shoes.

Can we see a picture of the stamp option? The stamp you cite reads a bit unusual. If '158' is indeed what the stamp says, we'll need you to weigh the window sash that these balances support. Give us that exact weight and we can work out the stamp option you need.