Mercury - Speedometer 45 MPH Boat Speed Monitoring White Face Brushed Bezel 79-8M6020063. OverviewThis 45-MPH speedometer gives you a clean, steady sense of your pace without bouncing around every time the hull shifts. The needle settles into a smooth swing, so checking your speed becomes a quick, natural glance instead of something you have to wrestle with. Out on the water, what you see on the gauge matches the feel of the boat, which makes cruising or trimming out a lot more relaxed. It's a s