Sash balance strength
A quick learner from Snohomish WA says:
July 18, 2014
Found S380 28" that looks like what I need. Not sure of the "strength" rating. My old one is stamped 2730G. Your choices are in the 26xx range of numbers. Mine is nominally a 3ft by 3ft single hung sash, vinyl, originally made by NW Aluminum in Washington state. I also need to top stop that secures into the sash panel channel where the lifter pushes up on the sash.
Paul from SWISCO responded:
July 21, 2014