There are two types with slightly different screw sizes. The size is the same. 75mm rubber casters, load capacity 60kg, Set of 4. I accidentally bought these, so I'm selling them. New, unused. - Model Name: ST-75RH - Diameter: 75mm - Load Capacity: 60kg/piece - Mounting Hole Diameter: 9.7mm - Screw Size: M16 x 40 - Quantity: Set of 4 Rubber casters, perfect for moving furniture and equipment. Set of 4. Photos 3 and 4 - Model Name: ST-75RH - Size: Diameter 75mm - Screw Size: M12x35 - Load Capacity: 60kg/piece - Mounting Hole Diameter: 9.7mm - Quantity: Set of 4 - Material: Rubber and metal - Application: Casters for moving furniture and equipment