Dimensional Pocket

This item is, in essence, a bag of holding in the form of a pocket. When placed against a surface, whether fabric, skin, or bone, and a command word is spoken, the pocket adheres to the surface and can only be removed by speaking the command word once more. Once attached, the pocket is invisible to the eye, but the wearer is always aware of its location and can reach for it unerringly. A see invisibility or true seeing effect reveals the pocket's presence, and detect magic can reveal its magical aura. However, the auras of items within the pocket cannot be detected with detect magic unless the pocket is open.
Beholders use dimensional pockets to carry important objects and to conceal magic items and weapons from foes. It can hold up to 1,000 pounds and has a volume of 150 cubic feet. The mouth of the pocket can expand to fit items up to 1 foot across.
A dimensional pocket cannot be removed unless the command word is spoken or the wearer dies, but contact with the extradimensional space to which the pocket is connected can be suppressed with a targeted dispel magic or antimagic effect. A favorite tactic of beholders fighting beholder spellcasters is to use their antimagic cones to prevent their enemies from accessing their dimensional pockets.
Moderate conjuration; CL 9th; Craft Wondrous Item, Leomund's secret chest; Price 9,000 gp.
Source: Dragon #313