You might want to dig around in the Concentrates & Portables sections....settle in for some light reading lol. Some of the "pens" are trash, others are working....and the devices are evolving at light speed. Currently using RBA's (rebuildables) seems to be in vogue - For those you'd want a mod or at least a variable setting ego style at minimum. A regular 510 battery (cigalike) wouldn't cut it. If you go to mods and RBA's please read up on battery safety as there is some risk playing with ohms/volts/watts.