It is possible to wear their armor on PC via editing it in Construction Set (Setting their armor to Playable).

Their armor appears as though it is made from the same material as the obelisks.Be warned: with every heart inserted into an obelisk, a Knight will spawn. These hearts can be used with obelisks to shut them down. Unlike all other Daedra in the game, they drop Hearts of Order rather than Daedra hearts.

Some tales say they were once mortals who worshiped Jyggalag and turned their flesh hard and rough as crystal and turned themselves into mindless minions of the ruler of logic and order. They are trained to be masters in swordsmanship, archery, and magic making them some of the most powerful Daedra. According to Sheogorath and Haskill, the Knights, much like their Prince, do not have a single original thought in their heads, making them perfect soldiers of Order. They are humanoid in shape, seemingly slightly taller than most humanoids, wear crystal armor and wield crystalline swords, which they seem to wield with great skill.

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