The Elco UltraCon (Tapcon concrete blue screws) masonry fastening system offers optimal performance in concrete, brick or hollow block whether anchoring electrical boxes, clips, wood headers, plywood, furring strips, insulation, etc. Cold formed, carbon steel anchors, precision-cut carbide drill bits and high-quality installation tools all work together to provide excellent pull-out and shear values. UltraCon screws feature nail points and high-low threads with v-notches to ease installation in concrete brick or block. Each carbon steel screw is coated with Stalgard® finish to provide superior corrosion resistance: no red rust or other base metal corrosion even after 800 hours of 5% neutral salt spray exposure (ASTM B117). Formerly sold as Tapcon® Screws for 26 years – Now as UltraCon Approvals: Current Miami-Dade, Florida NOA number available upon request. Made in the U.S.A.