MW Window Balance Replacment

A handy person says:
No clear markings other than a patent number : 5737577

Looks to be similar to your block and tackle 850 product with the exception of the top which is metal on your product. Nearly all of the plastic top anchors in my house have broken. Curious to know if your product is a good replacement for these (and addresses the issue of the plastic anchor) or if there is a more robust alternative balance that would work. The current balances are varied in length but include 24.5", 28.5", 34.5". The foot or bottom is black and 1.25" on all.
User submitted photos of a window balance.
Profile picture of Paul
Paul from SWISCO responded:
Thanks for posting. I agree, this looks like our Series 850 crossbow balance. However, the manufacturer stopped developing these with that plastic top hook. They now use a metal screw bracket. You can still use our balance, but you will also need a 26-200 screw plug. This plug inserts in the old hole in which your top hook would go, converting the jamb track to one that can be used with the new screw bracket.
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)