"Only if it turns out that reality is actually nothing more than a holographic illusion created by the interplay of subatomic particles on a vast two-dimensional membrane."
This article covers a subject that has been deemed non-canon by either the author or the Back to the Future licensees, and thus should not be taken as a part of the "real" Back to the Future universe.
Marty McFly holds the electric hoe in his right hand, and the car battery that powers it in his left.
The electric hoe was an invention of Emmett Brown.
It was perfect for weeding, but since it took a lot of energy, it was powered by a large car battery which the user had to wear.
