Traditional incandescent lighting illuminates around the perimeter of the dial 4 in 1 gauge design saves valuable real estate on your dash while allowing you to monitor critical parameters 12 and 16 volt compatible, well-suited with nearly every street car or race car electrical system Auto Meter’s race proven air-core electric instruments provide quick and accurate readings while keeping hazardous fluids outside of the vehicle Gauge kit includes 1/8” NPT pressure sender, 1/4” NPT adapter, 1/8” NPT temperature sender, 3/8” and 1/2" NPT adapters, bulb and socket assembly, red and green bulb covers, mounting hardware, and detailed instructions for installation