The 8-inch Heavy Duty Caster Wheel with Double-Locking mechanism and lockpins is a sturdy, safe, and reliable scaffolding caster. Designed to be used on scaffolding frames or outriggers these allows the user to move their scaffolding around the job inside and outside. The heavy-duty casters are also usable on most other standard scaffolding frames. They're built from industrial-strength rubber and mounted on cast-iron hubs with grease-fitting adapters for easy maintenance. Each wheel can support a total weight of 750 pounds and is built primarily for use on concrete floors.