Courtesy Padding
From BelegarthWiki
Courtesy Padding: The padding on any non striking surface of a weapon. The padding is applied to prevent accidental injury when on the battlefield. This goes on a halfed weapon such as a flail, axe, mace, spear, or glaive. The purpose of this padding is to protect form accidental contact, and is not a valid striking surface. Usually only 1-2 layers of foam is needed so core cannot be felt by a weapon checker.
Courtesy padding near the striking surface of a swung weapon should often have nearly as much padding as a striking surface (specifically in the case of flails and weapons with minimum striking surfaces).
From the Book of War:
1.3.2 All non-striking surfaces must be padded adequately to prevent personal injury from incidental contact.
See also: Basics of Weapon Checking