SRD:Amulet of Inescapable Location
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Amulet of Inescapable Location: This device is typically worn on a chain or as a brooch. It appears, to magical analysis, to prevent location, scrying or detection or influence by detect thoughts or telepathy. It seems to be an amulet of proof against detection and location. Actually, the amulet gives the wearer a –10 penalty on all saves against divination spells.