Kids can challenge by spiining the tops and whose spins the longer time.<br><br>Comes in 4 pcs per set.<br><br>Approximately 2.5 cm (1 inch) in Diameter. (see picture compared to coin)<br><br><img src="http://gdetail.image-gmkt.com/216/716643883/2015/6/3906320c-0ff4-4173-80fb-68b66cf28d2d.jpg" undefined=""><br><br>