28B USB counter balance #, 29 inches long, 1/2 inch wide

Hello,

Thanks for your post! This window balance appears to be a match for the S378-29 Channel Balance. Be sure to double check that the shoe has a  7/8" depth.

Our 2820 stamp should work for you. A pair of these will support a sash weighing 12 to 16lbs.

Close up view of the S378 balance shoe