A modern shotgun slug is a heavy projectile made of lead, copper, or other material and fired from a shotgun. Slugs are designed for hunting large game, self-defense, and other uses. The first effective modern shotgun slug was introduced by Wilhelm Brenneke in 1898, and his design remains in use today. Most shotgun slugs are designed to be fired through a cylinder bore or an improved cylinder choke, rifled choke tubes, or fully rifled bores. Slugs differ from round-ball lead projectiles in that they are stabilized in some manner.