Abe Jenkins developed the Mk. III Beetle armor to act as an agent in C.S.A operations; the armor was designed for solo operations and to make it unclear if he was the original Beetle due to the large differences between the armor designs.
Leila Davis, the former villain known as Hardshell, began wearing this armor when Abe abandoned it for the MACH-II Armor. She took the Beetle identity and operated as a member of the government Redeemers team until she and the armor were crushed by the villain Graviton.
A student called Gary Quinn later stole another copy of the armor from the Commission on Superhuman Activities and, with two students using older models of Beetle armor, joined the Initiative and Thunderbolts.
A team of criminals called the Repo Squad also wear modified Mk. III Beetle armor, or something that at least has a similar construction and appearance. How this armor was constructed without the assistance of Jenkins or the CSA is unknown.