Yes they are, and they work awesome at 3.7 volts. Using them on my altsmoke alpha and kgo bats and damned impressed. I still prefer my ego-t LR 'b' slightly for flavor and amount of liquid capacity, but these cartos are as close to awesome as it gets in my book. Oh and the "draw"...that is about as close to a cigarette as I've had since I started vaping.