Mix Part A and Part B in two separate vessels, heating each to 78 C. Slowly add Part A into Part B with stirring. Continue mixing and begin to cool when uniform. Add Part C at 50 c, continue mixing and cooling. Add Part D at 40 C, continue cooling and mixing. Pour at 30 C. Note: This rich luxurious night cream has a soft even texture. "merquat" 550's unique action revitalizes dry skin with deep penetrating moisture while giving a gentle smoothing effect, which lasts thorough the night.