Per4m EAA Xtra Amino Acids Full Spectrum EAA Sugar Free & Vegan 30 Serve, 420g. Who are Per4m?. To complete a truly rounded formula EAA XTRA also features precise doses of Taurine for hydration, Vitamin C for immune support and Citrulline Malate for ammonia removal helping you train harder and recover faster from hard hitting training sessions.