Product description ITW Red Head Tapcon, Type: Tapcon, Style: Large diameter zinc plated, Size: 3/8" x 4", Package Quantity: 50 per box From the Manufacturer Red Head Large Diameter Tapcon 3/8 X 4 Inch Anchor is a high performance anchor that cuts its own threads into concrete. The anchor bodies are made of hardened carbon steel and zinc plated, Grade 5. The anchors have a finished hex washer head with anti-rotation serrations to prevent anchor back-out, and the head of the anchor is stamped with a length identification code for easy inspection. The anchors should be installed with carbide tipped hammer drill bits made in accordance to ANSI B212.15-1994. Use standard ANSI bits instead of proprietary bits, which will reduce the chances for anchor failure due to incorrect bit usage, and will cut costs. The Large Diameter anchors install in less than half the time of wedge anchors or adhesive anchors, by simply drilling a pilot hole and drive the LDT anchor by hand or impact. They remove easily, no torching or grinding required to remove anchors. The Red Head anchors have a single piece design, no nut and washer to assemble, and more threads for better thread engagement and higher pullout resistance. The Large Diameter Tapcon anchors have closer edge/spacing distance than mechanical anchors, and higher loads in shallow embedments. Specs: Anchor Diameter - 3/8 inch; Socket Size - 9/16; Drill Bit Diameter - 5/16 inch; Effective Length - 4 inch; Max. Thickness of Material to be Fastened - 2-1/2-Inch inch.