1) Aventail 2) Camail 3) Hood 1) Aventail 2) Camail 
armour for the neck, attached to the helmet
• (n.) That part of a helmet which is intended for the admission of air, -- sometimes in the visor.
See Aventail
Vent'ail noun [ Old French ventaille , French ventail . See Ventilate , and confer Aventail .] That part of a helmet which is intended for the admission of air, -- sometimes in the visor. Spenser. « Her ventail up so high that he descried Her goodly vis...
In armour, a ventail was the lower movable part of the front of the helmet, which admitted air for breathing, the upper part being the visor.