The USSSA Thunder Heat softball is not nearly as susceptible to compression changes under increased temperature 100\xB0 F and decreased temperature 40\xB0 F compared to .40 .44 and .47 poly care softballs. This translates into a much more uniform and consistent compression ball from Spring play thru late Summer. UPC 026307430807Model Number: 4U-531 Archive | Link To Ballgloves Price Check |