The ViAir 10003 medium duty air system is perfect for medium duty applications like HornBlasters air horns, load-leveling, and occasional tire filling. This is the perfect onboard air unit for our HornBlasters H4 kit. This kit will fill up to 33 inch tires no problem and provides a hefty two and a half gallons of air. This single part supplies you with everything to install an extremely reliable, and sophisticated onboard air system. The 10003 kit includes a large 2.5 gallon air tank, a quick-refill 325C air compressor, and a dash panel gauge with system control.