I have one, Called fifty-one Duo! I love it. I got 2 cigarettes (batteries built in) a charger, and a membership card for 60$ at the local tobacco shop. then you buy the filters (with the nicotine) in the 5 for around 15$. One filter is supposed to be equal to about two packs. The make the nicotine in different milligrams. From 16 mg to 0 mg to help you quit. I can smoke at work so I use mine there, and it works! I love it!