Coil balance stamp location

Hello there!

Thanks for reaching out to us. From what I can see here, it looks like you might have the 15-177. You'll want to compare our specifications with yours to confirm they align. The stamped weight code is usually printed on the coil spring's tongue as well. 

If there aren't any or they're too faded to read, you'll have to divide the sash weight by the total number of springs in the window to determine the proper spring weights. 

Alternate image for 15-177