I found this on the site where I purchased my second iTaste. It might be helpful information.
Smart, stylish, innovative and packed with features, the Innokin iTaste V3 Express Kit represents a whole new approach to vaping! The unique and elegant square design is manufactured to the highest standards by Innokin and has received great reviews since it's launch. The iTaste V3 Express Kit features a standard 510 connection w/eGo threads making it compatible with just about any tank/cartomizer with a 510 or eGo connection thus offering truly versatile performance!
This superb device is much more than just a battery and comes packed with useful features. It has a powerful 800 mAh polymer li-ion pass through battery design with the voltage adjustable at the press of a button in one volt increments from 3.3-5v, with the voltage displayed on a high quality mirror finish LCD display. Not only that, but the iTaste can measure and detect the resistance of just about any cartomizer and will suggest the optimum voltage range that should be used for best results and display the relevant information on the LCD screen - take the guesswork out of variable voltage vaping and find the sweet spot for any device with ease!
The new power feature introduced with the V3 is variable wattage mode. This is the first device of this compact size to offer variable wattage from 6-11 watts in .5 increments. Once you set your desired wattage level, no matter what resistance atomizer you attach, the iTase V3 will adjust the output automatically.
And the features don't stop there, it also is equipped with a puff counter to monitor intake and measure the performance of the battery or your chosen cartomizer, a colour changing power button that indicates the remaining battery life, short circuit protection with 10 second cut off to prevent accidental discharge, 3 click on/off deactivation and pass through charging technology that allows you to charge the unit while vaping. Everything you need to enjoy your favourite flavour in your preferred tank/cartomizer and obtain optimum performance!