Portable Forge (3.5e Equipment)
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Portable Forge: A portable forge is found as an iron plaque with a relief depicting a forge. The plaque weighs one pound. On a command word, this scene expands into a burning brazier full of coals, billows, and an anvil, along with masterwork metalsmithing tools.
Once "unshrunk" (activated by command word), the forge remains in operation until reactivated to shrink. There is no time limit on the use of Heat Metal and the equipment contained within. A crafter can usually only use a production item for 8hrs per 24hr day (check with your DM for other time restraints/increases.)