Max Hard is designed to mimic the actions of the prescription erectile dysfunction drug Viagra. By simulating the action, Max Hard is able to help men achieve longer, firmer erections. Viagra acts by limiting the enzyme PDE-6 in the body. Max Hard acts to limit this same enzyme thereby extending the duration of the erection and its strength. By limiting this enzyme, blood stays in the penis longer causing a firmer erection. Yohymbine (from Yohimbe) in MaxHard drives blood to the penis and L-Arginine and L-Citrulline maintain this blood level in the penis via the nitric oxide pathway. This is a relatively new science and none of our competitors have L-Citrulline which continues the action of L-Arginine longer. 60 PILLS PER BOTTLE Only one pill is required per dose