Outfits and Headgear are cosmetic only items. You can select 1 out of 4 outfits at the character creation screen. You can obtain outfits by completing some Pursuits, some Missions or purchase them from the game store.
Outfits are the entire appearance from the neck down and Headgear is the head only.
Acolyte of the Guiding Light
Headgear
Transferred if owned in Defiance Classic
Antlers
Headgear
Solstice Strike Arkfalls during the Christmas Event 2014 or Radiant Solstice Supply Crate
Buckled Capotain
Headgear
Cyberclaus
Outfit
Wreck the Halls Pack during Solstice Strike
Transferred if owned in Defiance Classic
Happy Pumpkin
Headgear
Halloween Event 2014 or Blackened Hellfire Supply Crate
Liberty Infiltrator
Outfit
Paradise Patriot Pack during the Midsummer Mutiny Event
Transferred if owned in Defiance Classic
Liberty Infiltrator
Headgear
Paradise Patriot Pack during the Midsummer Mutiny Event
Transferred if owned in Defiance Classic
Pith Helmet
Headgear
Heartbreaker Supply Crate or Minor and Major Colony Courtship Arkfalls (Valentine's Event 2014)
Stitched Pumpkin
Headgear
Halloween Event 2014 or Blackened Hellfire Supply Crate
Stratotech Defiance 2050 [Source]
3PL9 WDFG DKPR 9LE7 P7Y7 [Redeem]