oN Serious Mass:-HIGH CALORIE WEIGHT GAINER Serious Mass is the best weight gainer ever have With 1,250 calories in one serving and 50 grams of protein for muscle recovery per serving , this Mass powder basically used the goal for post-workout and between the meals shake for increasing your muscle size. If u want to increase your size then use of this stuff develop your physique completely.And Serious mass is the award winner of best weight gainer.