CV stack is a product design to increase potency of harness and men to have incredible erection during sex to last hours. Contains 20 mg of Tadalafil and 20 mg of Sadalafil . Because it’s sublingual bypass the digestive system and easy in the liver works immediately. You don’t have to wait hours to take a fat or interfere with the food and digestive system goes directly to your blood string and last very long time