Vinyl Window Screw
The GRK vinyl window screw is a fastener and shim rolled into one
The GRK vinyl window screw is a fastener and shim rolled into one. When driven through the mounting hole in a vinyl replacement window, the screw captures the wall of the vinyl extrusion between a built-in lip and the underside of the screwhead, allowing the window frame to be adjusted in or out until it’s plumb. GRK sells the star-drive screw in several lengths, with or without a white powder-coated finish on the head; that’s handy for situations where the fasteners would be visible. Pricing starts from about $14 for a box of 100 screws.