The 3rd age platelegs are a part of the 3rd age melee set. Requiring level 65 Defence to wear, they have the second highest defence bonuses of all non-degradable melee leg slot items, only surpassed by the justiciar legguards. 3rd age platelegs are a possible reward from treasure trails, and cannot be bought in stores nor made through the Smithing skill.
They are roughly on-par with bandos tassets for melee defence, however 3rd age armour emphasises slash and crush defensive bonuses and lacks a strength bonus. Due to its price and lack of offensive bonuses, they are very rarely used for combat.