Designed after Apollo 12 astronauts Pete Conrad and Alan Bean had difficulties lugging their equipment significant distances to and from their Lunar Module, the MET primarily functioned as a portable workbench with a place for hand tools and their carrier, cameras, spare camera magazines, rock sample bags, environmental sample containers, and the portable magnetometer with its sensor and tripod.
The majority of the payload of the MET consisted of part of the Apollo Lunar Surface Experiments Package (ALSEP).,[2] including a portable magnetometer, as well as various tools and space to transport samples.
The biggest challenge for Goodyear was that NASA specifications required the inner tube be inflated to 1.5 psi on the Moon surface; a difficult task.
Goodyear solved the gauge pressure problem by having NASA partially inflate the inner tube with nitrogen so that on the Moon it reached 1.5 psi.
The later Lunar Roving Vehicle demanded wheels or tires that could handle a much greater weight and could travel much farther than the MET.