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Armor works in a specific manner. Consider combat armor, which has a damage threshold of 8 hit points and a damage resistance of 60% against laser attacks. (8 hp/60%)

The way armor works is like this: if you are wearing combat armor and somebody hits you with a laser rifle, you will receive x amount less. Say that if you're wearing the Vault 13 jumper, which has no protection whatsoever, and the enemy uses the laser rifle and hits you for 42 hit points of damage.

Take the same situation with combat armor on. The armor will naturally deflect 8 hit points of damage because of the damage threshold. Now only 34 hit points remain. The armor can resist 60% of that damage. Multiplying 34 by 60% will give you 20.4, and rounding that down will give you 20. You'll only take 20 hit points of damage with the armor instead of 42.

Name	Resistances*					AC	Selling price	Weight	Special effects/Description
	N	P	L	E	F
Pressed Vault 13 Jumper	N/A	N/A	N/A	N/A	N/A	N/A	N/A	??	Since this is the starting equipment it is lacking resistance modifiers and damage threshold.
Leather Jacket	0/20	0/10	0/20	0/20	0/10	8	300	5 lbs.	If you are a male and are wearing this, at the Raiders' camp, many people will think you are Death Hand. Adds several interesting conversation options.
Leather Armor	2/25	0/20	0/20	0/10	0/20	15	800	8 lbs.
Metal Armor	4/30	4/20	6/75	4/25	4/10	10	1000-1670	35 lbs.
Tesla Armor	4/20	10/80	19/90	4/10	4/20	15	4500	35 lbs.
Combat Armor	5/40	4/50	8/60	6/40	4/30	20	6000	25 lbs.
Brotherhood Armor	8/70	7/60	8/70	8/40	7/50	20	< 6000	25 lbs.
Power Armor	12/40	10/40	18/80	20/50	12/60	25	12500	85 lbs.	Adds 3 to strength, cannot be taken from dead wearing power armor, special dialogue options from people in Hub
Hardened Power Armor	13/50	13/50	19/90	20/60	12/60	25	15000	100 lbs.	Adds 3 to strength.
Children of the Cathedral (COC) Robes	N/A	N/A	N/A	N/A	N/A	N/A	90	10 lbs.	You can completing the entire Military Base level (required to beat the game) while in the robes by tricking all of the mutant guards by saying that you are a member of the Children. The COC members will believe you. Ditto for the Cathedral.

Resistance key

N	Normal
L	Laser
F	Fire
P	Plasma
E	Concussion
AC	Armor Class

* Please note that the labels for the lists of armor resistances are abbreviated. The first number is how many HP can be reduced and the secondary number is the percentage as explained above. So 2/25 is short for 2 hp / 25%.

To the right is a key for the abbreviations used for armor resistances. Just because a piece of armor is effective against Normal damage does not guarantee it will also effectively protect you from Plasma. Be weary of these variations and the types of damage your foes can deal.

[edit] Availability

Item	First seen at	Merchants that sell it
		Killian, General Store (Junktown)	Beth, Gun Store (Hub Downtown)	Jake, Jake's Weapons (Hub Old Town)	Gun Runners (LA Boneyards)
Pressed Vault 13 Jumper	You are wearing it at the beginning of the game.	Since this is your starting equipment it is unbuyable.
Leather Jacket	Vault 15, locker in the living quarters to the south on the 2nd floor.	Yes	Yes	No	No
Leather Armor	Raider camp, standard issue for other Raiders.	Yes	Yes	No	No
Metal Armor	Raider camp, Garl is wearing it	No	Yes	Yes	Yes
Tesla Armor	Cathedral, Tower level 4	No	No	No	No
Combat Armor	Hub, available for purchase (or you can kill the guards and swipe the armor).	No	No	Yes	Yes
Brotherhood Armor	Brotherhood of Steel; anyone in that building who look like they have combat armor on.	Unbuyable*
Power Armor	Brotherhood of Steel door guards; Darrell is only one wearing airtight helmet.	Unbuyable*
Hardened Power Armor	Nobody is wearing it, but looks the same as standard power armor.	Unbuyable*
Children of the Cathedral (COC) Robes	Jain is wearing them.	Unbuyable*

* Please refer to the section below for the exact details on how to obtain this piece of armor.

[edit] Special methods for obtaining armor

There are many pieces of armor that can be found or made without requiring a visit to one of the stores.

Item	How to obtain
Combat Armor	You can kill the guards at the Hub and swipe the armor from them.
Brotherhood Armor	Ask Talus and he'll give you one for free.
Power Armor	Repair it from Kyle or get the suit after completing.
Hardened Power Armor	Miles can harden the regular Power Armor for you in the Adytown in the LA Boneyards if you fix his hydroponic farm.
Children of the Cathedral (COC) Robes	Pick these up from the Church armory in the Hub.