Crystal Ball of True Seeing is a legendary wondrous items in D&D 5e. It requires attunement.
Wondrous item, legendary (requires attunement)
The crystal ball is about 6 inches in diameter. While touching it, you can cast the scrying spell (save DC 17) with it.
***Crystal Ball of True Seeing.*** While scrying with the crystal ball, you have truesight with a radius of 120 feet centered on the spell's sensor.