This device appears to be a normal container for holding burning coals, however, if detect magic is used, a dweomer is present. It enables a wizard to summon an elemental of 12 Hit Dice from the Elemental Plane of Fire. A fire must be lit in the brazier-one round is required to do so. If sulphur is added, the elemental gains +1 on each Hit Die (1d8+1 hit points per Hit Die). The fire elemental appears as soon as the fire is burning and a command word is uttered. (See the Monstrous Manual accessory for other details. Fire Elemental)
In Ravenloft: The elemental cannot return to its native plane unless it finds a normal escape route from Ravenloft. If the elemental is freed somehow from control, it attacks the summoner.