The transformable mobile suit MSZ-006 Zeta Gundam developed by the AEUG resistance group was originally considered far too complex and expensive for mass production. But Karaba, the organization that served as the AEUG's terrestrial forces, took note of the Zeta Gundam's effectiveness and redesigned it to create the mass production type MSK-006 Zeta plus (later redesignated as the MSZ-006A1). Because this machine was intended exclusively for use in the atmosphere, its space flight systems and atmospheric entry features were eliminated. However, its cost performance ratio and flight capabilities were superior to those of the prototype Zeta Gundam. Instead of the flying armor used by the original Zeta Gundam, the Zeta plus was equipped with variable geometry wing binders similar to those of the MSN-00100 Hyaku-Shiki. These wing binders improved the flight characteristics of the wave rider form, giving it a cruising range of hundreds of kilometers, and in mobile suit form they could be used for AMBAC maneuvering rather than simply becoming dead weight. The Zeta plus was also equipped with two thigh beam cannons, which were connected directly to its movable frame so that energy supply and fire control could be performed without using the mobile suit's hands. The first Zeta plus rolled out in November of UC 0087, and the new machine was assigned to Karaba units such as the 18th Tactical Fighter Aggressor Squadron (18TFAS) based aboard the carrier Audhumla. Karaba eventually deployed about 20 machines, three of which were painted in white and orange test colors for demonstration purposes. Some of the Zeta Plus A1s remained in service in U.C. 0096, and were stationed at certain Earth Federation ground bases such as the Cheyenne base. During Bright Noa's investigation of said base, two guarding Zeta Plus A1s were immobilized by Tri-Stars team's RGM-96X Jesta and RGM-96X Jesta Cannon.
