... with special power adapter and 3.7 V li-battery, the input voltage of the product is only 5 ... it costs less than 5 W power(200 hours for usage just cost 1 KW), but it brings far ... than any other similar products.4. Easy using: design for optional charging, USB or power adapter at home , li ... computer, too. It also can use mobile power (li-battery) to supply outdoors, which can keep continuous usage 3 ...