Flail (weapon) in the context of "Heavy cavalry"

A flail is a weapon consisting of a striking head attached to a handle by a flexible rope, strap, or chain. The chief tactical virtue of the flail is its capacity to strike around a defender's shield or parry. Its chief liability is a lack of precision and the difficulty of using it in close combat, or closely-ranked formations.

There are two broad types of flail: a long, two-handed infantry weapon with a cylindrical head, and a shorter weapon with a round metal striking head. The longer cylindrical-headed flail is a hand weapon derived from the agricultural tool of the same name, commonly used in threshing. It was primarily considered a peasant's weapon, and while not common, they were deployed in Germany and Central Europe in the later Late Middle Ages. The smaller, more spherical-headed flail appears to be even less common; it appears occasionally in artwork from the 15th century onward, but many historians have expressed doubts that it ever saw use as an actual military weapon.