Ok, several years ago the first vapers only had cigarette-size
batteries with poor battery life to use. Some of them came up with the idea to modify flashlights to use as large e-cigarettes with larger, longer lasting
batteries. The word "mod" came from this and has carried forward to this day.
So essentially a "mod" is any
e-cigarette battery holder which uses replaceable rechargeable batteries. This can include mechanical (no circuit board) or regulated variable voltage (with a circuit board), or something like the iTaste MVP which has an internal non-replaceable rechargeable battery charged with a USB charger. Mods are also called APV's (advanced personal vaporizers).
Advancing Up the Vaping Ladder to a Mod


Provari (regulated mod) - Caravela (mechanical mod) - iTaste MVP (regulated mod)