This MT3 is a bottom coil 1.5ml clearomizer with a metal tip. It produces great vapor and replacement coils are available in 1.8 ohm & 2.1 ohm resistances.
This is a 2.5 mL clearomizer that is filled from the top. An upgraded device for the more than casual user that has decided 1.6 mL of E-juice is not enough.