Window Balance 25DS 32

Hi there!

It looks like you have either our S351-26, with a 15-002 bottom attachment, or S390-26, with a 15-001 bottom attachment. Take a look at the image below to determine which balance you'll need. 

As for the stamp on your metal channel, the number after the "DS" usually indicates the precise sash weight. In your case, it would be 32 pounds. A 2565 stamp option supports a sash weighing 30 to 33 pounds so if your sash is indeed 32 pounds, this option should be fine for your window. You can always weigh your sash on a scale if you'd like to be 100% sure. 

If you have any questions just let us know! 

Comparison of the S351 and S390 balance shoes.

After years of use, the shoe tends to wear a little, which may make the depth a little less than what it once was. In your case, it may have once been 1-1/8" and simply wore down to 1-1/16".