Tom from SWISCO responded:
May 11, 2020
Hi there! Based on your old stamp of 26-4, you probably need to use our 2640 stamp option. A pair of S350-27, 27" balance with stamp 2640 will carry a window sash weight range of 19 through and including 26 lbs. As long as your sash weight falls in that range then it should be perfect. |