A handy person from Wa says:
June 8, 2016
HI, My balance has "30 3 GTC CMC 4" printed on it. It's not convenient for me to weigh the sash. I'm looking at the 30" series 385 channel balance. Can you tell me which spring option to choose?
Tom from SWISCO responded:
June 9, 2016
A stamp of 30 3 usually corresponds to our 3030 option. I would double check your length, it should be 31".