They’re supposed to be useful, little items that allow you to get the fun of a magic item, but keep the power on the lower side. Keep in mind these are meant to be super amazing. This lasts for 1 minute, but ends immediately if they take damage or someone uses an action to shake or slap them awake. On a hit, the target suffers the effects of the Sleep spell. In either case, make a ranged attack against the creature, treating the sand as an improvised weapon.