Aventail
Réf: camail cdj_361300

The aventail is a balaclava of stitches, the aventail became independent of the coat of mail from the end of the XIIIth century, protected the head, the neck, the shoulders, as well as the top of the chest and the back. Going down on shoulders, already covered by the coat of mail,it constituted a second level of particularly useful protection during battles, because risk was big to see the blade of a sword sliding on the helmet and breaking clavicles.

http://www.echoppemedievale.com/cale_matelassee_ref:_lnc_cp-08/739-2-1-c.html