If you've been prescribed oxygen therapy, it's essential that you get the dosage you need. This is why it's important to purchase an oxygen concentrator from a reputable seller. Everyone is looking for a bargain, but lower prices and easy access to oxygen concentrators can spell trouble.
Amazon can be a great place to shop for just about anything. Medical supplies, especially sophisticated equipment like oxygen concentrators, are a different story. Products that require a prescription cannot be sold on Amazon, and are against their seller regulations.