It is the screwing bottom coil heads replacement for Kanger EVOD BCC Clearomizer.
EVOD clearomizer has the same bottom coil heating system, same ego threading, same metal tube with viewing windows and great performance as kanger MT3 clearomizer. But EVOD's bottom coil head and metal base is detachable, so it will be less expensive to replace a coil. When the coil head dies, you can keep the metal base and replace only the mini coil head.
EVOD clearomizer can work well on most eGo/eGo T/eGo C batteries.