We have designed the AresAir Surgical Helmet to create an economical, practical and modular solution. We have a product for which you can choose the power supply from your local market or probably you already have for your phone or tablet. No issues for transportation of battery, no paperwork, and the most important is no additional costs. We suggest a 2 amp Li-Ion power supply with a USB port which has a minimum 10,000 mAH. A power source with these minimum specs will work with the ultimate efficiency up to 8-9 hours