How heavy is "heavy"?

Question

My spiral balances have been replaced at least once by the previous owner and the tip color is red. However, the windows measure 41"x30" which makes them larger than normal. So do I want the green or black tip S600-29 balances?

Paul · Accepted Answer

With you bathroom scale, weigh your window sash. If it weighs up to 20Lbs, use red,  if it's between 21 to 30 lbs, use blue, between 31 to 40lbs, use black.