The kestan mace head was a steel sphere and this was attached by a metallic chain to a steel haft or handle. The head was generally ribbed or had flanges. With a straight mace, where the spherical head is directly attached to the handle, the adversary can judge the direction of the blow and take parrying action, but when the mace head is a mobile sphere attached to a chain, it is very difficult to judge the direction or angle of the blow and parrying or evasive action requires much more skill and effort.