M.A.S.S. Builder (Multi-Active Strengthening System) is a veterinarian developed formulation designed to support optimal body condition and build lean muscle. M.A.S.S. Builder's unique amino acid blend supports feed efficiency while another component support appetite. It is a supplement for all classes of horses to help maintain healthy body weight.

M.A.S.S. is the first supplement designed to support healthy weight that combines Gamma Oryzanol, L-Lysine, Threonine and Fenugreek for maximum efficacy. This unique formula is a non-steroidal product that is veterinarian recommended to support healthy weight and lean muscle development in the horse.

M.A.S.S. is the only supplement of this type to include Fenugreek, a natural and effective substance that enhances the appetite in horses.