7 Color Turbo Boost Gauge Smoke Lens 12 Volt back Lit PSI Rotates between 7 colors - White, Blue, Red, Green, Yellow, Aqua, Purple Vacuum Scale 0 to 30 inches of HG/ Pressure Scale 0 to 20 PSI Silver Face OD 2 1/4" (Requires 2" Hole for Flush Mounting) Includes Mounting Hardware and Pickup Tube Backlit for High Visibility Night Time Operation