[ Item specifics ] Product : Piano Caster Cups Material: Plastic Color: black Type:Piano Castor Cups > Made High Quality Heavy Duty Plastic Material Designed for use with upright piano > Underside of each cup is lined with felt pad have sound-proof antiskid effect > Designed to be placed under a piano's legs in order to protect floors and carpets > Protects wood floor and carpet from caster damage > Material: Plastic; Quantity: 4pcs Package Includes: 4x Piano Caster Cups