MATERIAL: The swivel stem threaded casters are made of durable thermoplastic elastomer (TPE) and high quality steel, the surface with the chrome plating process is rust and corrosion resistant, which can last for a long time SIZE: Threaded rod bolt metric size is 6mm in diameter and 15mm in heightM615mounting height is about 39.5mm, wheel diameter is 25mm LOAD CAPACITY: Each caster has a load capacity of 15kg, and the 4-pack caster has a maximum capacity of 60kg, allowing for the transport of heavy items. TPE material avoids scratching your floor and makes it quiet 360 DEGREE ROTATING: 360 degree swivel casters make it easy to move around and the fixed stem makes it easy to set up PERFECT FOR: Suitable for replacing carts, kitchen cabinets, storage shelves, laundry carts, coffee tables, workbenches and other movable furniture