The Lyman Shotgun Bullet Mould / Sabot Slug - (Use with STD Wads) is constructed from solid leaded steel, machined to an extremely fine finish, and then heat treated. For top reloading, the mold offers hardened steel pins for alignment to ensure years of solid casting.The sprue plates are made from solid steel ground flat and with tempered steel spring washers and screws, held firmly in place. Compared to molds made from iron, the break-in time is cut in half. In addition, the mold is perfect for slugs that require no rifling, including hollow base Foster-style slugs.