4 Pack Black Twin Swivel Castors Specifications: (4 casters per pack) Steel socket included Item No.: RBSP40-S5 (4) Color: Black with Silver Stem and Silver Socket Material: Plastic, Steel Stem, and Steel Socket Applications: Soft floor coverings (i.e. carpet) Dimensions: Wheel Diameter: 40 mm (1 5/8") Stem Height: 38mm (1.5") Load Capacity: 100 lbs Brand: