Philips Respironics Simply Go Portable Oxygen Concentrator Includes: Simply Go Oxygen Concentrator Carrying case Mobile cart 16 rechargeable lithium batteries Smart charger/ recalibrator for batteries DC and AC power cords All for $600 If you where to buy this all new would cost you over$8500 Great for people with copd or difficulty breathing as it’s portable so you can take it with you everywhere to help give you oxygen.