EHP Labs PSI is a supplement designed to help maximise pump. If you enjoy the feeling of fuller, tighter, vascular muscles, PSI is for you. It contains a unique blend of blood flow enhancing ingredients which will help to dilate blood vessels and drive oxygen and nutrients to your working muscles, while taking away unwanted metabolites which can cause fatigue. The result? Not only will your muscle cells swell in size helping to stretch the fascia between muscle and skin, this will also help your muscles to grow. You also get the added bonus of a more aesthetic and larger muscle. Being stimulant-free, the PSI can easily be stacked with other pre workouts such as EHPlabs RPM for best effects.