Modern 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