Lawson window replacement of channel balance.
A handy person from cudjoe key , FL says:
April 12, 2016
Part # on back of Lawson balance is 2920, what is Swisco replacement # ??
Tom from SWISCO responded:
April 13, 2016
I'm not sure! All that stamp tells us is how strong the spring is. I recommend that you look at our Channel Balance Home Page and follow the steps in order to find the Series that best matches what you have.