A series of protective glasses are used to protect human eyes from the Loom of Fate.
During the Loomworld, the Fates built the Loom Temple of the Fates and placed the Loom in a room with humans guarding it. To protect the Humans, protective glasses were given.
When the Legends broke into the Temple, John and Astra knocked out the guards and took their glasses.
John and Astra wearing the glasses