channel balance needed

Take a look at our S380-16 or S385-16. These look a lot like your existing balance. The only difference between these two replacements is the depth, or 'heel-to-toe' measurement, of the bottom nylon shoe, so compare both with your old hardware to see what matches best. 

You'll need to choose a stamp option, which designates the strength of the spring calibration inside the balance. Look for a stamp code on the metal channel that designates this stamp option. If there is none, or you are uncertain, obtain the exact weight of your window sash. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on the product page. Let me know if you have any other questions.