Helmet

• Internal Database: All armours. Adding it to raider armour needs higher skill, as there is nowhere to store data in a metal bucket.
• Rad scrubbers: T-60. Living in a world dominated by radiation, the Brotherhood does whatever it can to reduce the rads its soldiers are exposed to.
• Recon sensors: T-51, T-60. Advanced recon tech brought in with the T-51 and carried across to the T-60.
• Sensor Array: see Internal Database.
• Targeting HUD: X-01. X-01's equivalent of recon sensors. Relies on the fact that the X-01 uses a digital visor rather than a bulletproof viewport (or at least, that's how I'm explaining the glowing eyes).
• VATS Matrix Overlay: X-01. Partnership between Enclave and Vault-Tec resulted in the latter's targeting tech being integrated into the X-01.
  

• Blood cleanser: All armours. Installed to allow soldiers to take their daily psycho rations without worrying about addiction. In raider power armour this is replaced by the ‘chem recirculator’, which makes all chems last 25% longer.
• Core assembly: All armours. It doesn't take a genius to link the suit's primary capacitor bank to the fine motor servos, although it's advised you know your way around a circuit diagram before you attempt this. In T-45 armour, this has the added advantage of reducing the suit’s power drain.
• Medic Pump: T-45, T-51. Prototype medic power armour. Eventually abandoned due to the system burning through meds at unacceptable rates, and on several occasions lethally dehydrating a soldier in the field.
• Emergency protocols: T-51, T-60, X-01. An upgrade to the T-45's medic pump, without the need for valuable medicines.
• Jet Pack: T-51, X-01. An early idea that was abandoned for power saving reasons. Brought out of storage for the X-01. Makes the reward at the end of the Brotherhood questline a bit more special.
• Kinetic Dynamo: T-60, X-01. The ceramics of the T-51 were too inflexible to accommodate this mod, but the metal-plastic laminate of the T-60 was more suitable.
• Reactive Plates: X-01. Incorporated into the X-01 after the T-51's ceramic casing was found to be vulnerable to massive physical impacts.
• Stealth Boy: X-01. Stealth power armour is exactly the sort of thing a committee would think of.
• Tesla Coils: T-60, X-01. Tesla armour was first trialled with the T-60.
• Welded Rebar: Raider. Some raider clans organise gladiatorial melee fights between power armoured opponents.
  

• Hydraulic Bracers: All armours. Tuning up the hydraulicsin the arms is so simple even a (smart) raider could do it.
  

• Optimised bracers: T-45, T-60. Brotherhood Paladins wholike to get up close and personal with abominations, but not yelled at by Proctor Teagan for wasting fusion cores, swear by these mods. Installed in T-45, these reduce fusion core drain and improve reload speed.
• Rusty Knuckles: raider. Clearly, the raider philosophy of“more rust = better” still holds. A proper soldier doesn't let their kit get
  rusty!
• Tesla Bracers: T-51, T-60, X-01. What was originally an ad-hoc mod made by soldiers in Anchorage got added to the T-60, and carried forwards.
  

• Calibrated Shocks: T-60. Brotherhood long-range patrols need to carry all the kit they can, as there is no logistics corps backing them up. Pre-war, this was never much of an issue.
• Explosive Vents: T-51, X-01. Developed in conjunction with the jet pack.
• Kinetic Servos: T-51, T-60, X-01. Later model sof T-51 converted excess kinetic energy into electrical power for moving the suit's fine motors. This was later fitted to all following models.
• Optimised Servos: T-45, T-51, T-60, X-01. After the fuel-guzzling T-45 was retired, methods of reducing power drain were investigated. When installed in T-45, this mod reduces fusion core drain and improves movement speed.
• Overdrive Servos: T-45, X-01. The T-45 was famous for its power management issues, which were not helped by overly-enthusiastic soldiers removing the limiters from the leg servos. As a prototype, the X-01 was never built with efficiency in mind.
  

• Explosive Shielding: removed. Effect has been moved to the T-51f ‘Minesweeper’ armour.
• Lead Plating: Raider. The unsealed suits of raider power armour have no inherent rad resistance, so raiders looking to scavenge radiated areas (or fight glowing ones for fun) need to make additional modifications.
• Photovoltaic Coating: X-01. The finest minds of the Cambridge Polymer Labs team were able to create the piezonucleic armour - this will require similar effort and an even more advanced testbed.
• Prism Shielding: T-45. An emergency modification made to T-45 armour after it was discovered that untreated steel conducts heat from energy weapons really well.
• Titanium Plating: T-45, T-60, X-01. Unable to be applied to the T-51 as it would obscure the silver ablative layer the armour uses for energy resistance. Other models have their resistances built into the material so this is not an issue.
• Winterised Coating: T-51. We're taking back Anchorage with the T-51b!
• X-01 EMP Shielding: X-01. Implemented by the Enclave once the inevitability of nuclear war became apparent.