Vibra-Jacket

The Vibra-Jackets, also known as floaters, were a technological device, shaped somewhat like a life-vest, that allowed the wearer to vibrate their molecules out of synch with our reality, even travelling to alternate realities. They figured prominently in The Verdant Vigilante storyline. Created by Jolt City University professor Marita Costello and her assistant, Dr. Fatima Tarif, the jacket prototype was stolen by an associate of the untouchable druglord Samson Snapp. Snapp modified the Vibra-Jackets so previous fail-safes that "snapped" them back to reality would be ineffective and began to mass-produce them.

Crime Wave
Snapp armed himself, his dealers, and myriad other gangs and criminals throughout Jolt City with the jackets. The police and costumed heroes like the Green Knight and Darkhorse alike were rendered helpless, unable to apprehend crooks that could become immaterial at will. This brief period of unchecked terror came to a halt when Roy Riddle and the Green Knight received a Vibra-Jacket from an anonymous "friend"-- in reality, Derek Mason, a Snapp dealer who had secretly been working with Dani Handler to bring Snapp to justice-- thus allowing Dr. Fay to reverse-engineer a new fail-safe. At long last, the police and the costumed adventurers could get to work.

Snail-Earth
Snapp had been mass-producing the jackets on an alternate earth populated by French-speaking snails after enslaving their population. They were freed through the combined efforts of the Green Knight and Darkhorse, and Snapp was arrested on the capital crime of waging inter-dimensional warfare. He escaped this charge, however, when the physical evidence against him was destroyed and the human witnesses were murdered by Vibra-Jacketed assassins-- both events orchestrated by Snapp's rat in the law enforcement, Assistant District Attorney Jack Fisk. (The snails of Snail-Earth had such short lifespans that none of the eyewitnesses were still alive even a few weeks hence.)

The Hordes of Apelantis!
Snapp allied himself with the Aquatic Ape Empire-- a race of undersea primates that lived in the city of Apelantis-- providing Vibra-Jackets for their newest invasion of the surface world, starting with America and Jolt City. This invasion was thwarted through the combined efforts of Martin Rock (uniquely not in costume this time around), Derek Mason, Dani Handler, and Dr. Fay. The latter negated the Vibra-Jacket threat once and for all, and Snapp was arrested for treason.