Casey from SWISCO responded:
December 13, 2019
It's best to replace to the original screw size, if the screws are missing from the original hardware the following is suggested. The recommended screws for a wood window application is (2) #8 x 1" Phillips, flat head, sheet metal screws. The recommended screws for a PVC or Metal window application is (2) #8 Phillips, flat head screws (lenght to be determined by profile). |