Wand of Polymorph

From Dungeon Master's Guide, page 211. Found on Magic Item Table H.

Description
''Wand, very rare (requires attunement by a spellcaster). 1 lbs.''

This wand has 7 charges. While holding it, you can use an action to expend 1 of its charges to cast the Polymorph spell (save DC 15) from it.

The wand regains 1d6+1 expended charges daily at dawn. If you expend the wand's last charge, roll a d20. On a 1, the wand crumbles into ashes and is destroyed.