The Fuhattan Style Mod is manufactured copy of the original FUhattan, which is a variant of the Manhattan. Aside form it's staggering low price, this mod includes adjustable floating top pin, and adjustable bottom magnet switch. The contacts are all copper and the body is made of a lightweight aluminum alloy. This mod rocks - and it's performance is way way way better than you'd expect for a device of this price range. It has an 18650 sized battery tube and 510 connectors.