Honestly I have no idea on battery size. I came across it on another forum and since I do a lot of business with wordup anyway I knew I could trust them, plus at that price and a 15% off Halloween/moving sale I figured I would give it a shot. I'll be sure to update this
thread with my thoughts on it once I get it and use it a bit.
I'm already accustomed to using a 510 @ 6volts with my V3, and I had been thinking about getting an 801 adapter and trying that out anyway, so this works out even better. I'm thinking surely that battery life can't be that good, right? I mean, it's a 6volt pen style. A 3.7 volt pen style sucks with battery life....
Here's to hoping I'm pleasantly surprised!