USP Labs makes a few other supplements worth mentioning. I have also had good luck with Anabolic Pump when looking to build muscle fast or lose fat and get rid of belly fat. After running USP Labs Prime solo I ran it with Anabolic Pump and loved the results. Anabolic Pump is another natural Supplements for Muscle Mass that works great if you have problems with insulin sensitivity and fat gain while on a bulking program. In all I have been happy with their products for helping me and others gain muscle fast.