Here's the brazen bottle, from Encyclopedia Magica:
This item has the appearance of a highly -Burnished, brazen flask, shaped like a Klein bottle. The flask is corked and the cork has a red seal impressed bearing mystical runes. When uncorked, the symbols on the seal may be used to compel 1d6 djinni or 1d2 efreet into the bottle, which is then corked. When one creature is being compelled, the compulsion is at +4 effectiveness, for two creatures, the effextiveness drops to +1, and more than two creatures have normal saving throws.
The bottle may also be used to attempt to jug one of the following - a balor (+3), invisible stalker (+2), an air elemental (-1), a fire elemental (-2), or a minor fiend (+1). If forcibly compelled into the bottle, any of the above creatures (including the djinni and efreet) are in very foul moods when next uncorked (attacking with haste and ferocity). When found in a dungeon, or elsewhere, a bottle may already be occupied - at the DM's discretion. If a considerable time has elapsed since the being with compelled into the jug (say 1,500 years or so), the being may be so glad for its new-found freedom that it willingly serves the person who freed it for 1001 days. In some cases (a balor for instance), the liberated creature may attempt to destroy everything in the immediate vicinity.