Our balances are stamped 2840. However, our tilt windows weigh only 20 lbs, and the balances are so strong that the windows are easy to open, but very difficult to close. I want to replace them with ones with weaker springs, 2830. As you can see from the photos, the balance has no plastic end pieces, and the metal bottom of the balance rests directly on a screw in the window frame. Which of your balances would replace these?
