Speed Stacks Competitor Sport Stacking Set 12 Specially designed Speed Stacks Cups G4 Pro Timer and Mat The only cups endorsed by the World Sport Stacking Association (WSSA) for competition Winner of a 2018 Family Choice Award! The &quot;Family Choice Awards&quot; recognize the best in children's and parenting products. WSSA approved Timer Accuracy to 0.001 seconds Memory feature to save your best times Data port to connect to external display Includes 2 AAA batteries WSSA approved Mat &#039;Optimum&#039; stacking surface New timer mounting system