The CCell M3 is an ultra slim and compact 510 cartridge pen made of stainless steel to handle every day carrying in a pocket or bag. The M3 heats your cartridge only as you inhale with an LED indicator to let you know when it’s active. The M3 gets about 150 rips on a full charge of the internal 350 mAh battery and recharges quickly with the included USB 510 charger.