need window channel balance, width 1/2in, length 30 in. the 350 series appears to be the right choice however cannot determine if the 15-004 shoe and 19-002 top match mine.
stamp reads 29 9 nl bsi. also is there anything else i may need to complete the replacement
Tom from SWISCO responded:
May 9, 2016
I'm afraid that stamp does not help. The best way to confirm if the 19-002 and 15-004 match yours is to carefully compare the style and dimensions we show for each to your own. You will also need to weigh your sash to determine the proper option.