Wand of Fireballs

This wand has 7 charges. While holding it,
you can use an action to expend 1 or more of its
charges to cast the fireball spell (save DC 15)
from it. For 1 charge, you cast the 3rd-level
version of the spell. You can increase the spell
slot level by one for each additional charge you
expend.
The wand regains 1d6 + 1 expended charges daily
at dawn. If you expend the wand's last charge,
rolla d20. On a 1, the wand crumbles into ashes
and is destroyed.