Improved 500 gallon double planetary mixer is equipped with special “HV” high viscosity mixing blades. The “HV” blade design permits the mixing of extremely viscous materials up to 8,000,000 cps. This mixer includes the following features: stainless steel construction; full vacuum operation; jacketed mix vessel for heating or cooling; dual post air/oil hydraulic lift; and mix vessel on caster wheels. A variety of options including complete control packages, discharge systems, sanitary designs, etc. are available.