Now fitness-minded individuals can get exactly what they want in a ready-to-drink protein shake—high performance protein and more of it! MET-Rx® RTD 51 is the powerhouse of protein shakes. Each nutritionally advanced, ready-to-drink protein shake is packed to the max with 51 grams of protein featuring Metamyosyn® that helps support muscle.* Get shakin’ in your choice of delicious flavors.