Continuity mistake: When Jack and Lexi are in the jeep talking a car can be seen in the mirror, but when they pull over no car passes them.
Continuity mistake: When Captain Eureka puts out the fire at the pumping station, Jack's Jeep somehow gets on fire, but we are able to see where the fire went, and it didn't come anywhere near the road or the Jeep.
Chosen answer: It's basically just a type of suit that's made for whatever special project they're working on. No different than a lab coat, hazmat suit, fire coat, etc.