This E.R. Wagner plate caster has a pneumatic wheel, a flat base with holes for bolting or welding to an object, and a swivel design to allow movement with a 360-degree change in direction. A total-lock brake simultaneously prevents rolling and restricts swivel movement when the foot-operated lever is depressed. The plate caster's pneumatic wheel consists of a soft rubber tread on a three-piece steel hub with zinc plating, and it is fully inflated with air at 50 pounds per square inch (psi). The wheel provides quiet operation, protects floors, and has a cushioned ride, making it suitable for bearing delicate loads. The double row swivel construction with extra-large raceways provides durability.

Plate casters are wheeled mechanisms used to support and maneuver objects such as carts, racks, and dollies. Plate casters are named for their mounting system: they have a flat plate, usually with four bolt holes, that forms the top of the caster and attaches to the object. Plate casters vary in their maneuverability. Some are rigid and only roll at a fixed angle, while other casters swivel to allow a 360-degree change in direction. Plate casters may have brakes, and swivel casters may have locks to set them to a fixed angle. Casters may have single or twin (dual) wheels made from a variety of materials. Generally, wheels with hard tread material have a higher load capacity and roll easier than soft tread wheels, which provide quieter operation and cushioning. Load capacity for plate casters is also affected by tread width and wheel diameter. Plate casters are used on furniture, carts, shelving, appliances, scrap bins, production dollies, and utility trucks for material handling applications in a variety of industries.

E.R. Wagner manufactures casters, wheels, hinges, stampings, and tubular products. The company, founded in 1900, is headquartered in Milwaukee, WI.