Discrete yet powerful. It fits perfectly in the palm of your hand or even the coin pocket in your jeans.  Magnetic connector with built-in/attachable 510 thread (x2) Aluminum alloy housing Quality circuit board with multiple protections Inhale activated 550 mAh Li-ion battery for a longer life Subtle LED activation indicator Micro-USB charging with LED alerts Super-fast charge in under a 1/2 hour Dimension: 42x55x12.8 (mm)