Inogen One G3 Find your freedom to breathe anywhere, anytime without managing oxygen refills or carrying heavy oxygen tanks. The Inogen One G3 portable oxygen concentrator is your at-home or on-the-go solution for oxygen therapy, in a small and lightweight form. Take it with you around town, on the road, or on a cruise! Inogen One G3 Systems. G3 Accessories Compare Systems.
The amount of caffeine in one caffeine pill is equivalent to two cups of coffee. Caffeine pills may be beneficial to students who wish to stay awake for studying purposes. Caffeine pills may be beneficial to people who want to have more energy for exercising in order to lose weight. Caffeine can be ingested in pill form. People who take caffeine pills may have a hard time getting to sleep at night.
400 milligrams Up to  400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two energy shot drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks. Although caffeine use may be safe for adults, it's not a good idea for children.