The Cigreat KK Mod Device is an all mechanical mod device that includes no electronics other than the battery that is inserted. The K stands for King and it will certainly make you feel like one due to the outstanding performance and reliability. With this device there is very little that could ever go wrong that would cause you to be without a working e-cig. When the button is pressed, a mechanical lever inside the top of the tube completes the connection necessary to allow the battery to power the heating element in the tank above. Therefore, as long as the battery has some juice left in it then you can keep on vaping. Since it is a telescoping mod device, it is compatible with 18350, 18500, and 18650 batteries. It even comes with one Samsung ICR 18650 Battery rated at 2600mAh capacity and 4.2 volt output when fully charged. Product Details: Battery Brand - Samsung Battery Capacity - 18650/2600mAh Mod Tube Diameter - 24mm Mod Tube Length - 110mm Tank Diameter - 20mm Tank Length - 70mm (including mouthpiece) Working Voltage - 4.2volts (when fully charged) Liquid Capacity - 4ml Resistance - 1.4-1.6ohm Colors available - Rose Red, Platinum, Titanium, Silver, Copper, Pewter, Gold, Blue Kit includes: 1 x KK Mod Device Tube 1 x KK Mod Tank 1 x KK Mod Tank Replacement Coil Head 1 x Samsung 18650 2600mAh Battery 1 x 18650 Battery Charger 1 x User Manual