Window balances inquiry

Thanks for your photos. Based on what I see here, you have either our S351-25 or S390-25, depending on the depth of the bottom shoe. That's the only difference between them. I recommend measuring your shoe and referring to our dimensions to confirm the best match.

Another detail I'm uncertain of is the stamp. This is what determines how strong the spring is and the marking written on your balance does not correspond to any stamp option that I've ever seen. With that in mind, you may need to weigh your sash on a scale to determine what to pick. We have a chart on the S351-25 and S390-25 store pages that will tell you which option corresponds to which weight.

Comparison of the S351 and S390 balance shoes.