The All-Terrain Tractor Locomotion System was a caterpillar locomotion unit for droids built by Incom Corporation. With their 928 kilograms, such tread units were heavy, but they could still achieve high speeds with an average power usage. They were made of chromium-vanadium, steel, medium-carbon steel and aluminium, all of which were of med-high durability. Due to their components, those locomotion systems were also magnetic.