Info from users guide: CHARGING THE POWER DOME ELECTRICAL SHOCK! Exposure to water may cause electrical shock. Exposure to water and excessive moisture will also damage the unit and void the warranty. Charge your Power Dome in an upright position for a full 48 hours before initial use. The Power Dome can be charged continuously via AC adapter without damaging the internal battery. In order to prolong the life of the Power Dome (as with all lead-acid batteries), be sure to fully recharge the unit every 3 months even if the Power Dome has not been used. AC Charging Only use the AC charging adapter supplied with this unit. Make sure the supplied AC/DC charging adapter is powered by the correct voltage (110V AC or 220V AC depending on your country/region). 1. Make sure all Power Dome switches are off (including the Master Switch). 2. Open the dust cover on the charging jack. 3. Plug the DC end of the AC/DC charging adapter into the Power Domeâ€â"¢s charging jack. 4. Connect the AC end of the AC/DC charging adapter to the wall outlet. 5. The charging indicator will light up during the charging process. 6. When charge is complete, disconnect the adapter from the AC outlet first, then from the charging jack. 7. Replace the dust cover on the charging jack.

Dimensions (approx.) WxLxH (in.): 9.5â€ÂL x 6.5â€ÂW x 10â€ÂH