PLAY LIKE THE PROS DO - WILSON A1015 PRO SERIES SST BASEBALLS. Built for highschool and college athletes, the Wilson A1015 Pro Series SST Baseballs will help you and your team succeed on the field. It was constructed with SST (Super Seam Technology), which are seams that are raised 20% higher than those of others baseballs, which enhances the ability of pitchers and fielders. Your game never has to end.