Simpson Strong-Tie offers a full range of gas- and powder-actuated tools and fasteners designed to maximize jobsite productivity and operator comfort in most applications. The PDPAT is a hardened-steel, powder-actuated top-hat pin designed to fasten building components to concrete, steel and CMU. The PDPAT fastener has a 0.300-in. diameter head with a 0.157-in. diameter shank and a steel top-hat assembly for fast loading and centering of the pin in the nosepiece of the tool. PDPAT 1/2-in. Knurled-Shank Powder-Driven Top-Hat Pin (100-Qty) (Pack of 1000).