Maximum Strength. Now with Somatrin. Pro-Hormone Free. Testosterone Stimulator. Pro-Testosterone. Anti-Estrogen. Testosterone, Estrogen, and Growth Factors are the most potent anabolic hormones for increased muscle mass, strength gains, and cranked up sexual drive! Here’s why ISA-TEST is the breakthrough Testosterone formula you’ve been waiting for: Based on recent data, when combined with weight training and a healthy diet, may elevate Bioavailable Testosterone, reduce Estrogen, and improve Anabolic Growth Factors. New Rapid Bio-Diffusion Delivery Technology – starts working fast! Notice: This product does not contain any prohormones or pro-steroids.