Masters of Justice: Dr. Atomic

Eric Palmer was a renowned physicist and professor.   After stumbling onto a mass of white dwarf star matter that had fallen to Earth, he fashioned a lens which allowed him to shrink down to subatomic size or grow to the height of approximately 50 feet. Originally, his size and molecular density abilities derived from the white dwarf star material of his costume, controlled by mechanisms in his belt, and later by controls in the palms of his gloves. Much later, he gained the innate equivalent powers within his own body.

He still uses the belt if he has to shrink others down.