The MSB427103 Splice Box, part of the most diverse surface mount offerings available, is a solid brass mounting solution with a concealed wiring compartment. Featuring our Aurora Mount System (AMS) built into the splice box for maximum aim-ability and 360° of fixture rotation, the 2 1/2″ diameter box is secured to a mounting plate with set screws and sealed with an O-ring. The electrical splice is hidden inside the box for a neat, clean installation. The MSB427103 is ideal for attaching our luminaires to a flat surface, whether it is a wall, ceiling, or structure.