Modern green LED through-the-dial lighting provides clear visibility during nighttime use. Autometers Race Proven Mechanical Instruments Provide Trusted Accuracy While Being Simple To Install. No electrical system required for gauge operation - compatible with every street or race vehicle. Mechanical movements provide accuracy and durability even in the harshest environments. Gauge kit includes 1/8" nylon line 1/8" NPT compression fittings 1/4" NPT adapter mounting hardware and detailed instructions for installation