The GX-9901-DX Gundam Double X (aka Gundam DX, Double X, DX) is a mobile suit produced by the New United Nations Earth in After War Gundam X, piloted by Garrod Ran.

Technology & Combat Characteristics
The GX-9901-DX Gundam DX was created by mobile suit engineers of the newly formed New United Nations Earth (NUNE). NUNE recovered the wreckage of GX-9900 Gundam X used by Jamil Neate during the 7th Space War and transplanted some of its system to the new mobile suit dubbed Double X. Furthermore, as creating a completely brand new design was extremely difficult, the mechanics used the Gundam X as the base unit when developing the Double X.

An improved version of the Satellite System, the Satellite System Mk-II, was developed by the NUNE engineers for Gundam Double X. It consisted of six larger reflector panels on the suit's back, and several energy radiator plates on the limbs as part of the new improved cooling system to increase Double X's microwave energy absorption. Accompanying this increase in energy storage capacity, the single-barrelled Satellite Cannon was upgraded into the two-barrelled Twin Satellite Cannon, allowing Double X to unleash destructive force several times that of the Gundam X.