A toolbox can also refer to a large tool storage system, or tool chest combos, that includes multiple pieces. These systems are almost always made from metal. Most tool storage systems are painted steel, but some are stainless steel and aluminum. They include a top chest that has drawers and a top lid that opens on a hinge. The top chest is designed to sit on a cabinet, also called a rolling cabinet (rollcab) or rollaway. The cabinet sits on four or more casters and has drawers to organize tools. Other pieces can be added to the system or combo. A middle chest, also called an intermediate chest, can be placed between the top chest and cabinet for extra storage. A side cabinet with more drawers can be hung from the side of a cabinet. A side locker can also be hung from the side of a cabinet; usually with a door that protects shelves or small drawers.