Tilt window balance ID
Thanks for posting. I'm told by my colleague Steve that you purchased our S770-28, 15-169, and 15-170. This is the right hardware, but we usually custom make these balances here for you so that you don't have to assemble them yourself. It can be a bit tricky. That said, I'm happy to walk you through it.
First, lock the balance in a vice, draw the cord out, and lock it in the locking pliers. That will release the tension on the cord and allow you to swap the clip that comes with the S770-28 with our 15-170. When you release the locking pliers, make sure you're holding onto the cord tightly or else it'll fly back into the balance. It's under a lot of tension. We recommend wearing gloves and goggles, just in case.
Next, you'll need to remove the nylon screw way at the top of your balance and install a rivet in the top hole, same as your old balance. You can re-use your old S hook or purchase our 19-029.