Ehpro's Cold Steel 120w Mod in collaboration with AmbitionZ VapeR is compatible with three battery sizes which are 21700, 20700 and 18650. You'll be able to use an 18650 battery with the included adapter.
In addition, it offers the user a wattage output range between 5w and 120w. Not to mention, it has tons of other modes built in as well such as temperature control, Bypass, curve and volt mode. Another great feature to this device is that it can fire down to 0.05 ohm.