Source: Strixhaven: A Curriculum of Chaos

Wondrous Item, Common

A masque charm is a small silver pin. While wearing this charm, you can use an action to cast the Disguise Self spell (DC 13 to discern the disguise). Once the spell is cast, it can't be cast from the charm again until the next sunset. When casting the spell, you can have the spell last for its normal 1 hour duration or for 6 hours. If you choose the 6-hour duration, the charm becomes nonmagical when the spell ends. In either case, the spell ends if the charm is removed from you.