Diable Avionics
Diable Avionics is the American continent's single biggest arms manufacturer. Established as an aircraft manufacturing and development company decades before the Universal Century, they merged with several other military aerospace and naval manufacturers in the early 0010s and entered the military industry.
These days, Diable Avionics is everywhere in Britannia. They now are involved in the manufacturing of automobiles and other civilian vehicles (Diable Motors), personal and professional computers (Diable Systems), and heavy industry production equipment (Diable Industrial), and have merged with or otherwise control several formerly independent military contractors. They also have significant reach in other civilian manufacturing fields, not always under the Diable name; many people would be surprised to find out just how much they control
Diable makes quite possibly the largest range of wanzers of any current manufacturer and continually pushes the envelope; their flying wanzer Gracilis is still unique. They also make non-wanzer military equipment, pushing into territory previously controlled by Anaheim, including replacement parts for Anaheim-made mobile suits. Anaheim hates this, but Britannia supports Diable so they don't have to pay the Anaheim markup when repairing their forces.