Through its subsidiary Simpson Strong-Tie Company, Simpson Manufacturing designs, engineers and manufactures wood-to-wood, wood-to-concrete and wood-to-masonry connectors; fastening systems; and prefabricated shear walls. Simpson Strong-Tie also offers a line of adhesives, mechanical anchors and powder-actuated tools for concrete, masonry and steel. The Simpson Dura-Vent Company, another subsidiary of Simpson Manufacturing, designs, engineers and manufactures venting systems for gas and wood-burning appliances. The company s common stock trades on the New York Stock Exchange under the symbol SSD. Simpson Manufacturing is headquartered in Dublin, Calif.