HUGREN, IMP lava tube is quit large about 5inches ,and heavy,i have a lambo-4 which is the same thing; also have a1300mah spinner made by vision,which IMO is a great mod for only 25$,I would get 2 so one could be on charger will using the other,I know by experance that the spinner give just good a prof. as my2600mah lambo ,at1/3 the cost, check out the eGo 18650 mod, they cost 22$ and reviews say they last a long time up to 4 days per charge they use a 2600mah battery, and can be charged with ego charger costabout 9$, also the spinner does not need any adaptors for differant atties or cartos, this is just my in put on this do what you think will serve your needs.....