A Flail is a class 1 weapon made to approximately parallel historical combat flails. It is distinctive in that the striking surface is "hinged" by rope or cloth from the handle, allowing it to wrap around shields and weapons to strike an otherwise protected target.
For instructions, see Constructing a Flail.
Flails are essentially a two-piece weapon, connected in some fashion. There is the handle, with a pommel, unpadded handle, and the rest of the haft, which must have at least some measure of Courtesy Padding. Fiberglass and kitespar are the most commonly used core materials, with PVC also occasionally being used, especially for rope-head flails (see below).
The flail head, the striking surface of the flail, is constructed entirely of foam, tape, and glue with no rigid core. It is covered in cloth, and attached to the handle by the chain.
The chain, which allows the flail head to move semi-independently of the handle, is usually formed either by a rope somehow embedded within the flail head and affixed to the handle, or by having the open end of the flail head cover extend down to the handle, where it is securely affixed with tape, using the cloth itself as a chain. The latter method is commonly referred to as a bag-head flail, while the former is a rope-head flail.
The chain must also be mostly covered in dingleberries, small loops of foam covered in tape which act to thicken the chain and prevent it from wrapping around people's wrists.
Many people, including the hardcore movement, object to flails as they are commonly constructed and used, accusing them of being skill on a stick or string cheese. In particular, kitespar-cored bag-head flails with minimal haft padding can be constructed to weigh very little, allowing them to be quickly flicked from the wrist and difficult to block. It is also pointed out that these flails bear almost no resemblance to their historical counterparts.
Other people, both flail-users and sword-users, defend flails, saying that their historical realism is no worse than other Belegarth weapons and that they simply require a little additional skill to defend against.
From the Book of War:
1.4.5. Flails must conform to the following:
220.127.116.11. The striking surface must haves a minimum circumference of fifteen (15) inches measured on separate axes.
18.104.22.168. The maximum chain/hinge length is six (6) inches.
22.214.171.124. The maximum overall length is forty (40) inches.
126.96.36.199. The hinged part of the flail must be padded with foam to keep the chain from easily entangling a Weapon or body part. No more than 1 ½ inches of chain may be exposed.
188.8.131.52. Only one hinge per flail is allowed.
Additionally, a flail is always considered a class 1 weapon, and must abide by all applicable rules accordingly.