Simpson Strong Tie Outdoor Accents Hardware. The Simpson line of black outdoor accent hardware is a line made up of black powder coated hardware for use in builing outdoor structures as well as a variety of projects. As a matter of fact, Simpson has a few different plans available including a very cool farm table. One of the key components of the Outdoor Accent line is the structrural screws and the hex washer head. When used together you get the appereance of a wrought iron assemlby, all done with a simple fast drilling screw.