Sierra Sterling 3" tachometer. Sierra Part #63474P.• Brushed aluminum dial, black graduations/numerals, black pointer• Scratch-resistant curved glass lens with polished stainless steel, near-flush bezel• Perimeter lighting • Dial Range: 0-7000 RPM• Tachometer/Hourmeter (Electric): O/B & 4-Stroke Gas Engines• Sender Code: O/B ALT. COIL• Tachometer: Mariner 30 & 40 HP (2-cylinder) engines require a module (Mercury P/N 17461A2)• Voltage: 12V DC• Current Draw: 0.10 - 0.15 A• Operating Temperature: -40C to +70C• Ingress Protection: IP65• Bezel O.D.: 3.74"• Housing O.D.: 3.39"• Hole Size: 3.43" Near-flush bezel Perimeter lighting | Sierra Sterling 3" Tachometer in Black