The document discusses testing of low global warming potential (GWP) refrigerant alternatives to replace R-404A in commercial refrigeration systems. Two alternatives, DR-7 and DR-33, were tested in a reach-in freezer and a display case with an external condensing unit. DR-7 has a GWP of 246 and is suitable for smaller systems, while DR-33 has a GWP of 1410 and is suitable for all system types. Testing found that both alternatives provided equivalent or improved energy efficiency compared to R-404A, with comparable operating pressures and temperatures. The alternatives show potential as low-GWP replacements for R-404A in commercial refrigeration applications.