Bevor

He who lookes you in the face, ſaith he ſees you, though the reſt of your bodie be within your cloathes, and if you, being an ὁωλομάχος a cataphract in your proteſtantiſh πανοπλία [panoplía, suit of armour] should for fear pull downe your beuer before you come into the liſt, your Aduerſarie for all that might light vpon your (  ) vnleſſe you bring with you Giges his ring, ſo to make your ſelf inuiſible; [...]

Source: wiktionary

Since gorgets completely encircled the neck, they were usually more articulated than the bevors to allow for some movement of the neck and head. Bevors typically were open in back but extended up above the wearer′s jaw on the sides and front. Use of a bevor or a gorget depended upon the type of helmet the knight wore[…].

Source: wiktionary

For heavy field use a reinforcing breastplate was sometimes added, together with a wrapper over the upper bevor.

Source: wiktionary

Many helmets had an upper part joined with hinges to a bevor, which protected the knight′s lower face and jaw.

Source: wiktionary