GRK Fasteners Top Star No. 14 X 3-1/8 in. L Star Zinc-Plated Shim Screws 100 pk

GRK adjustable Top Star shim screws, is in fact a screw within a screw that allows you to install wooden doors or windows without the use of shims. The quick and easy system reduces labor and allows for hassle-free adjustments to ensure plumb installations. Our product is suited to meet the needs of both professional contractors and weekend warriors making the job easier for one person. Fine adjustments are as simple as the turn of a screw, even after years of use and settling.