Zeon's Zimmad Company converted one of the two Prototype Doms into the YMS-09D Dom Tropical Test Type. The newly rebuilt and modified Dom Tropical Test Type mounted a coolant storage tank on its backpack to better regulate the mobile suit's temperature in the desert heat.
This zeonography is the 1:144 Prototype dom and tropical test type variation. It is beautifully done. However, the downide is that the figure has very limited posability.
This required the mount latch of the heat sword to be moved to a vertical position behind the left shoulder, as opposed to the original horizontal or diagonal positioning in other Dom models. The new Dom Tropical Test Type also featured a short-range communications antenna on its head. These additional features helped the Dom Tropical Test Type maintain better combat efficiency in tropical climates.
The desert warfare unit Caracal Corps, which was stationed in North Africa, would convert twelve of their Doms in such a manner, including the personal unit of Zeon ace pilot Major Roy Greenwood, whose Dom Tropical Test Type would be nicknamed "Thunder Cat" because of the lightning bolt designs on its frame. Advances from the Dom Tropical Test Type would also later serve as the basis for the upgrades of the MS-09F/trop Dom Tropen.