From the Manufacturer's Label:
WHAT ANIMAL STAK™ IS: Hard gainer. You’re a hard worker and you give it everything you got 24/7 but the gains are hard to come by. As a classic hard gainer, you train big and you eat big, but you have little to show for it. Animal M-Stak is a non-steroidal product geared specifically for you. Through its unique set of properties, most notably “nutrient-partitioning”, Animal M-Stak helps you maximize your lean gains with greater efficiency and effectiveness.** Work hard. Don’t gain hard.
Manufactured by Universal.