This listing is for one set of 4 - 8" x 2" Steel Wheel Casters, Pack of 4 Swivel Casters. The Swivel Caster Forks contain Double Ball Raceways, Zinc Plated Finish for added rust resistance, 1/4" Thick Cold Forged Yoke Legs and Mounting Plate for extra heavy duty applications. The Mounting Plate size is your industrial standard 4" x 4-1/2" overall size. These plates will need 3/8" Attaching Bolts which are not included. These Steel Casters are great for Platform Trucks, Commercial Use, Industrial Applications, and even Food Service Applications. These Wheels come with a heavy duty 3/4" Roller Bearing with a 1/2" Spanner Bushing with Food Grade Grease. Metal / Steel Wheels are great for High Capacity applications. Each 4 Inch Steel Wheel is Precisely machined semi-steel with a Tensile Strength of 30,000 PSI and a Temperature range from -45 F to 600 degrees F. The 4" Steel Wheels have a solid core hub design for extra strength and Durability. Our Semi-Steel Metal Wheels have a Zerk Grease Fitting in the Hub of the Wheel, Zerk Axle, and a Grease fitting in the Swivel Raceway for 3 easy lubrication points for easy maintenance to extend the life of these steel casters and wheels. Metal Caster wheels or Steel Caster Wheels are commonly used in many Vintage Applications and DIY Projects where one may want a vintage or industrial style caster to compliment their furniture or project. Each caster holds 1,250 lbs capacity making a Set of 4 able to withstand up to 5,000 lbs. Steel wheels should not be used on Hardwood Floors, Tile, or Bamboo Floors as they could leave marks or tear up softer flooring. We always recommend steel wheels to be used on smooth concrete surfaces or a surface you don't mind possibly scratching.