My scrap metal/duct tape e-pipe! lol, you truly can make one out of anything.
So, I used a 2 dollar aluminum pill fob from a local pharmacy. Actually have em to carry spare 18350 on my key ring. They house a battery perfectly as they come. For the mod, I cut the bottom out and drilled a small hole in the side, for my positive pin connection.
The small metal strip is part of a hollowed out ego battery. That serves is my negative connection. As the tube is still connected to the ego 510 threading.
The pill fob and the bottom metal connection is insulated by the bottom of a 10ml juice bottle that was razor blade'ed to perfection.
The center pin is an old broken aga-t positive post and a spare nut ground down to fit appropriately and placed inside the ego/510 connector.
The opposite side of the aga-t post(now my center pin) attaches to the hole drilled in the pill fob.
For the switch, I drilled a hole in the already existing pill fob lid. Then used an air passage "center pin" from a old ce2 for the switch "shaft". Harvested a spring out of a bic pen and cut it in half and wedged it into the pill fob lid to secure it. Due to the recession in the pill fob lid, it hovers over the battery. until forced down.
Then wrapped it all in black duct tape to hold everything together. Also screwed a 5ml dct ego cone on to the ego threading before taping, to match the aga-ts' diameter better.
So yep it works
comes with 0.6v drop, woot. not too shabby for make shift.