R600a, is refrigerant grade Isobutane, a natural, or “not in kind”, refrigerant suitable for use in a range of refrigeration applications. The use of R600a is increasing due to its low environmental impact and excellent thermodynamic performance and it is now the refrigerant gas of choice in domestic and small commercial refrigerators. It is non-toxic with zero ODP (Ozone Depletion Potential) and very low GWP (Global Warming Potential).