The T-45 powered combat infantry armor was the first design pressed into service in the Sino-American War,[​1] with its first deployments taking place on the Alaskan Front to counter the Chinese offensive. The speed at which it had to be deployed, less than two years after the development of power armor began, resulted in the creation of a stop-gap model utilizing existing technologies and manufacturing techniques. This temporary solution would eventually become the mainstay of American power armor units, especially as subsequent upgrades reduced the impact of the mobility problems that plagued the early production runs.

• Brotherhood Power Armor / Lyons' Pride Power Armor, standard issue for the East Coast Brotherhood of Steel, but less common in the Mojave Wasteland
• Army Power Armor, it has a US Army band on each shoulder.
• MP-47/A Prototype Medic Power Armor, a variation of the Army power armor equipped with a Mister Gutsy-like onboard artificial intelligence.
• Outcast Power Armor, a variant worn by Brotherhood Outcasts.
• Tribal Power Armor, a unique version of the standard power armor which has been painted and adorned with various tribal emblems
• Scorched Sierra Power Armor, an NCR variant used by Colonel Royez on Long 15.
• NCR Salvaged Power Armor, a suit made with salvaged metal and does not require Training to wear.

• T-51b Power Armor
• Enclave Power Armor
• Remnants Power Armor