Special-Lite® Thresholds provide a weather seal for the bottom of an exterior door, which helps keep rain water, snow and insects out of your building. All thresholds will be fabricated to fit from jamb to jamb. We supply thresholds shipped loose for field installation. Our standard threshold is ½” x 5”(12.7mm x 127mm). Threshold clips will be supplied with all thresholds to ease installation.