Overflux Capacitor

The Overflux Capacitor is an drop within the   drop chance category. The item can be obtained from the Sven Packmaster if the player is at least Wolf Slayer 7. It is used in the crafting recipe for the Overflux Power Orb.

Obtaining
An Overflux Capacitor can drop from the Sven Packmaster if the player has reached. It has a  chance to drop from the boss.

Trivia

 * Between the Scythe Blade (After 0.7.5 Update), Digested Mosquito, and the Overflux Capacitor, the latter seems to be worth more than the former two, going for higher prices on the auction house, This is because the Capacitor is required to make the Overflux Power Orb, which, when compared to its fellow elite tier slayer items, Mosquito Bow and Reaper Scythe, is more useful. The Orb applies several buffs to the player whereas the Mosquito Bow barely beats the power of the Runaan's Bow, as well as the Reaper Scythe being nerfed, making it the best of the items.
 * This item's name might be a reference to the Flux Capacitor in Back To The Future