Searching for Have remove coils from window one is mark 406j and other sa406 do I need both and what is the difference

Looks like you have the old Simonton brand coil balance assembly. They no longer made this, but we offer a more modern replacement that I think works just as well. I actually think it works a little better, since it's not prone to breaking in half like your old one is.

The video below will go into more detail. This will explain exactly what parts you need to buy and how you can install them in your window. Just note that you will need the exact weight of your sash on hand in order to calculate the proper spring strength. You want to divide that weight by how many springs support the sash, then pick accordingly.