Simple and compact! I love this multiple use. Battery jumper, phone charger, flashlight, USB plug, etc. I bought one for a friend three years ago and it saved her from a sudden start with a stranger in a dark garage late at night. Just think of the safety factor for one of them. I upgraded my old big, clunky jumper box (which worked fine) to a lithium jumper that's 1/3 lighter, 1/3 the size, and 4 times more powerful. Mine starts a 10 liter diesel and is a little bigger than the one I bought for a friend but it's sooo cheap. I needed a larger size for a new 6.6 liter diesel truck. Remember your battery will drain when it's worst, so do yourself a favor and buy it now! It also fits perfectly anywhere in your vehicle.