28 " Block and Tackle window balance

Thanks for contacting us. We don't have a 1:1 match for this balance but take a look at the S795-28. This comes attached with a T-lock shoe but you'll have to swap it for the 15-224 inverted link (sold separately). However, your 27 7 stamp doesn't match up with any of our options. Can you weigh the window sash on a scale and tell us the precise weight?