Mail of the Fiend
A chest piece emblazoned with demonic glyphs
Medium Armor Set: Fiend Armor Dyeable ID: 901
Follower Damage +4%, Concussive Damage +5%
A strange set of armor, crafted by a cult of maniacs. A forbidden sect of passionate fools that insanely believed they could become that which they worshipped, a demon of the abyss - if only they dressed as one first (and sacrificed as many souls as possible).
About Mail of the Fiend
Mail of the Fiend is a Medium armor piece in Conan Exiles. It provides 59 armor, with 1 heat resistance and 1 cold resistance. It belongs to the Fiend Armor set.
Medium armor is the middle ground: enough mitigation to survive mistakes while keeping reasonable stamina for dodging, which fits most Strength and Agility builds.
Its set or piece bonus reads: "Follower Damage +4%, Concussive Damage +5%".
On the details, it weighs 13.78, has 430 durability, and can be dyed to match your character.
Within the Fiend Armor set its 59 armor value ranks #1 of 5 pieces.
Verdict: Overall Mail of the Fiend is a Medium piece best used as part of the Fiend Armor set, which rewards a balanced playstyle.