Promethium platelegs are a leg armour used in the Dungeoneering skill. They are made by smithing Promethium bars. They require a Defence level of 90 to equip. To make a Promethium bar you need 1 Promethium ore. Promethium platelegs require 3 bars to be made, needing 97 Smithing and giving 283.5 experience. It is dropped by the Flesh-spoiler Haasghenahk and by forgotten warriors.