The CRL Window Adapter Channel is used to replace most single glazed aluminum sliding windows, many aluminum and steel casement, wood stop and wood putty windows. The channel is designed to accept a 1/2" (12.7 mm) sealed insulating glass unit. All the window frame component parts are reused. This adapter uses CRL Insulating Glass Glazing Vinyl. The corners may be fastened by using our adapter corners and #8 x 1-1/4" pan head sheet metal screws. A thin bead of CRL silicone sealant should be applied to the mitered corners to seal.