Window Balance - 770 Series

Question

I've been able to determine this is a 770 Series.....just wanting to make sure that I am reading the 'B' code correctly

User submitted a photo of a window balance.

Tom · Accepted Answer

This code actually doesn't match any of our stamps for the S770-28. I recommend that you weigh your sash on a scale to determine how heavy it is, then referring to the chart we show on the S770-28 store page.