Acan double hung window pivot tensioner.
Thanks for reaching out to us! We should be able to help with this coil balance assembly, but please note that we only sell the individual components separately, not together.
See our Series 15-111 pivot shoe, along with our 1/2" thick Series 160 coil spring and 15-150D double spring support. I recommend first checking to ensure that your spring is the same 1/2" thickness. If you need more than 2 springs (or fewer, for that matter) let me know and I can suggest a different support, too.
Gotcha, thanks for clarifying. If you only use one spring per side then I suggest the 15-150S single support. With a 1/2" thickness, the Series 160 sounds like the right part for the job.
I also don't have any idea how to remove the old components. There definitely isn't a cutout slot.
Sure, so as mention before your pivot shoe is a match four our 15-111. The coil spring connects to the shoe at the top; if you look at our photos you'll notice two round holes on top of the housing. What might be a little harder to see are two thin slots that bisect those holes.
The way the spring installs is to slide into that thin slot and then twist. The "T" shape at the end of the spring band will ensure that it doesn't slide back out. Hopefully that makes sense.
As for removing the assembly, you will definitely need a cutout. If there is not one already in the window then you will have to make one. The video below will show you how this is done.