LR stands for low resistance. It refers to the ohms of the atomizer or cartomizer you are using. 1.5-2.0 ohms works very well with a 3.7v device such as this, and I have got a lot of love for the screwdriver. The only reason I'm selling them is because I have quite a few. If your serious about wanting them, and use paypal, I will mark them as sold, and when you get enough post to PM, we can work out the rest of the details.
Edit:
Also while I like the look and
reviews of the lavatube myself, there's no guarantee there wont be problems, as it is a new unit on the market. The screwdriver is a tried and tested pv, and has proven to work for years with a little care.