besagews

Besagews are circular defences designed to protect the armpits, as part of a harness of plate armour. Armour without besagews might employ larger shoulder defenses, such as winged pauldrons or simply leave the mail beneath exposed.
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Small round "shields" that were laced to the mail at the shoulder to defend the armpit. Developed as augmentation to mail defenses in the late 13th century, they faded in popularity during the first half of the 14th century, disappearing completely by 1350 as spaulders began to serve the same purpose while at the same time defending the shoulder joint itself. During the latter half of the 15th century they made a comeback, added occasionally to tourney garnitures during the early 16th century.