Mercury - Speedometer 65 MPH Boat Speed Monitoring White Face Chrome Bezel 79-8M6020016. OverviewThis 65-MPH speedometer gives you a steady, no-nonsense read on how fast the boat's moving. The needle doesn't bounce around when you cross a wake or hit a little chop-it eases into place so you can catch your speed with a quick glance. Out on the water, it feels natural and lines up well with how the hull is running. It's a clean, simple gauge that fits right into a normal day behind the wheel.. Key