Potion of Gaseous Form

From Dungeon Master's Guide, page 187. Found on Magic Item Table C.

Description
''Potion, rare. 0.5 lbs.''

When you drink this potion, you gain the effect of the Gaseous Form spell for 1 hour (no concentration required) or until you end the effect as a bonus action. This potion's container seems to hold fog that moves and pours like water.