Connect BLACK Wire/Ground DIMENSIONS: Dimensions: 3.684 x 2.002 x 0.775”, (93.57 x 52.88 x 19.68 mm) • Connect BLACK wire on harness to chassis GROUND. Weight: 2.4 oz. (68.03g) Connect Wire/POWER ENVIRONMENTAL SPECIFICATIONS: • Locate a fused, constant 12 VDC power source and a suitable chassis ground.