Clear Visibility During Nighttime Use,Compatible With Every Street Or Race Vehicle,No Electrical System Required For Gauge Operation,Compression Fittings/Mntng Hrdwr/Detailed Instruc. For Install,AutoMeters Race Proven Mechanical Instruments Provide Trusted,Accuracy While Being Simple To Install,Modern White LED Through The Dial Lighting Provides,And Durability Even In The Harshest Environments,Mechanical Movements Provide Accuracy,Gauge Kit Includes 1/8 in Nylon Line/T Fitting/Vacuum Fitting