ITEM NAME:8pcs Black Vertical Piano Caster Cups Protector Rubber Pad Anti-Shock LLD PDT.Disperse the force area of the piano wheel and protect the floor from being crushed by the piano wheel. - Designed to be placed under a piano legs in order to protect floors and carpets. Product list: Piano mats 2 sets (1 set of 4 ï ¼Å’total 8 pcs).