FJC GUAGE SET Features and Benefits: Aluminum block design with sight glass Available with different lengths of hoses and choice of Quick or Manual Couplers Anti-flutter design gauges Additional access port Attractive clamshell packaging FJC's A/C Manifold Gauge Sets test automotive air conditioning systems by comparing the pressure readings between the "high side" and "low side"to manufacturers' specifications. Use this set to test, evacuate and fill automotive air conditioning systems. Color coding on gauges, valves and hoses ensure correct installation. Our manifold sets offer large gauges with impact-resistant lenses. Warranty: Call vendor for warranty