It saw relatively limited use by more elite and seasoned soldiers.

This model is substantially different from the earlier Mark II model.ДЄs an improvement of the Enclave's mainline power armor, the Mark II 'Tesla' variant is a modified Mark II 'Black Devil' with jery rigged tesla coils on the suit. It uses interlocking lightweight composites. The 'Black Devil' Mark II, for its signature look given to by the Brotherhood, is the mainline power armor used by the Enclave based out of Raven Rock in Washington D.C. This armor saw limited use with the Enclave's special operations forces before it ended its conceptualization phase.ДЄdvanced Power Armor Mark II 'Black Devil' It utilized lightweight composite and with more plating, without compromising weight. The X-02 is a prototype power armor developed by the Enclave in Raven Rock. It offered lightweight ceramic composites compared to the ceramic plates and metal plates of the Mark I. The Mark II was developed as an improved variant of the Enclave's mainline power armor before the destruction of the Oil Rig. This armor is seen as the Gannon Family Tesla Armor in Fallout New Vegas. It utilizes jery rigged capacitors on the exterior to help focus energy weapon shots. The Mark I 'Tesla' is a prototype power armor of the Advanced Power Armor Mark I.

This armor is further seen as the Remnants Power Armor in Fallout New Vegas. It was widely used as the Enclave mainline power armor before the destruction of the Oil Rig. The Mark I was developed by the Enclave and is made of a lightweight metal alloy with ceramic casting at key stress points. This armor is further used by the Enclave in its later years. It is primarily designed with a lightweight metal alloy and ceramic casting at key stress points. The X-01 is a prototype powwr armor developed by the Enclave before the Great War. It was intentionally supposed to also automatically dispense Stimpaks, but development never progressed that far. It automatically dispenses Med-X to the pilot along with an integrated AI personality. The MP-47, or Prototype Medic Power Armor, is a suit of T-45d that became a prototype model using experimental technology seen in Big MT. It is commonly used by Arthur Maxon's Brotherhood of Steel. It was developed in early 2077 by West Tek as a superior suit to replace the T-51b while sporting a similar aesthetic of the T-45d. The T-60 is a prewar power armor that saw extremely limited use. It was under heavy development in West Virginia and was casted in black titanium to further increase durability. It was spearheaded by a member of the T-45d development team and borrowed several elements of the T-45d. The EXC-17, or Excavator Class Power Armor, never entered production or left the prototype stages. Fallout, Fallout 2, Fallout 3, Fallout New Vegas, Fallout 4, and Fallout 76 It offered many, many advancements in technologies compared to the T-45d. It further offered increased protection than its predecessor, T-45d, by utilizing composite plates that were attached to a body suit. It was developed by West Tek like the T-45d. The T-51b Powered Infantry Armor is the pinnacle of prewar power armor. Fallout 3, Fallout New Vegas, Fallout 4, and Fallout 76 This armor is widely used by the Brotherhood of Steel's lower ranks and less advanced chapters and used by the US Armed Forces. It is primarily made of interlocking, hardened steel plates. The T-45d Powered Infantry Armor is the first in a long line of power armor used by many factions, both prewar and post war. Few post war factions can manufacture new suits, and much less create new suits. It saw wide development and use before the Great War by companies like West Tek and the United States Armed Forces. Powered Infantry Armor, or just Power Armor, is the staple armor of many post war factions, like the Brotherhood or Enclave.

Fallout 3 medic power armor