Blue and black face nitrous gauges with easy-to-see color graduations and a white pointer. Liquid filled NOS brand gauges feature an all stainless steel construction. Dry gauges have a stainless steel case with brass internals. Sniper brand liquid filled gauges are contstructed of a stainless steel case and brass internals, dry gauges are chrome plated steel case with brass internals. Gauges are available individually or in a gauge kit that included the gauge with a in-line gauge adapter. All connection fittings are 1/8" NPT