As the armet was fully enclosing, and narrowed to follow the contours of the neck and throat, it had to have a mechanical means of opening and closing to enable it to be worn.
The cheek-pieces opened laterally by means of horizontal hinges; when closed they overlapped at the chin, fastening by a spring-pin which engaged in a corresponding hole, or by a swivel-hook and pierced staple.
A reinforcement for the bottom half of the face, known as a wrapper, was sometimes added; its straps were protected by a metal disc at the base of the skull piece called a rondel.
[3] The armet reached the height of its popularity during the late 15th and early 16th centuries, when western European full plate armour had been perfected.
[6] The armet is found in many contemporary pieces of artwork, such as Paolo Uccello's The Battle of San Romano, and is almost always shown as part of a Milanese armor.
[7] The armet was most popular in Italy, however, in England, France and Spain it was widely used by men-at-arms alongside the sallet, whilst in Germany the latter helmet was much more common.