Shadow Cuffs  

You get the Hadean Abjuration: Hands for this in Einherjar in the armory crate after you defeat all the enemies in your chamber.

You need Cursed Cuffs and the Abjuration to get this.

The recipe for Cursed Cuffs is as follow:
-Earth Crystal

*Velvet Cloth x1
*Angelstone x2
*Karakul Leather x1
*Netherspirit Chain x1
*Platinum Silk x1
*Imperial Silk Cloth x1

the entire Shadow Coat Set gives these stats in all:

* Defense +109
* MP
* INT +5
* MND +5
* CHR +5
* Magic Accuracy +24
* Magic Attack Bonus +4
* Enmity -12
* Physical Damage Taken +12%
* Magic Damage Taken -3%
* Damage Taken +4%

For more information on Einherjar go to http://wiki.ffxiclopedia.org/Main_Page

Good luck on getting it :)