2 inch / 52mm radiator coolant temp gauge w/ sending unit.In-line black aluminum hose fitting with 1/8 NPT sensor port.100-300’F black face, tinted lens and illuminated red needle.Selectable 7 color LED back-lighting with color recall ability.1/8-27 NPT temperature sender passes signal to the gauge.7 color settings: blue, green, red, teal, yellow, purple, white.Sized by the outside diameter of the fittings outer raised lip.Includes detailed instructions and easy DIY wiring diagram.