Sanwa Supply SNC-COVER1 Black covers to smooth the movement of casters, set of 5. - Quantity: 5 pieces - Size: For 50-80mm casters - Color: Black - Application: Caster covers Thank you for viewing. I was using these to prevent my pet's paws from getting caught. These were helpful because I could move the chair without worrying about my pet. I am selling them because I no longer use an office chair in the same room. Instant purchase is welcome. No price reduction, please. I have two sets available, and the combined price is 4700 yen. Please feel free to contact me.