H2-WF is a probe droid companion capable of all 3 roles (tank, dps, heal) and can be ranked up to influence 50. H2 is the only companion in the game that drops as boss loot in a flashpoint. As of level 80, H2-WF is the best Tank Companion when parsed against a dummy.

You can find your own H2-WF within the Flashpoint: Nathem Conspiracy, when playing on any of the 3 available difficulties. H2 has an uncommon but not low chance of dropping from any of the bosses (including the bonus boss, a duo of Zildrog Followers found before the 2nd Boss).
The miminum level to use H2-WF’s inventory unlock item is level 10 and the probe droid pops right into your companion list, meaning that you don’t have to get all the way past KOTET to earn him in the story mode, you can get him as soon as you are groupfinder eligible for Veteran Flashpoints.

A cheap and easy way to level H2-WF to influence 50 is by trading your unused Jawa Junk on the Fleet in exchange for droid friendly companion gifts available at the green, blue and purple Jawa Junk vendors located at the Cartel Bazaar.

Unfortunately H2’s inventory item is Bound to Character, this means that if you want to use H2-WF on other characters you must also run them thru the flashpoint until you get the probe droid as a drop in your inventory again.

H2-WF’s appearance is based on the probe droids that spawn in the Temple Guardian Droid’s arena, the 2nd boss encounter of the Nathema Conspiracy where you must use these probe droids as cover from the Temple Guardian Droid’s spinning laser attack.