The R888 was a temporary fix for Speed World Challenge. Since Toyo did not have a 245/40/18 RA1 for the crews, they had to get the R888 DOT and brought over for the races. Since Toyo now has the RA1 in the correct sizes, the R888 is no longer brought over. It is the exact same compound as the RA1, just a little different tread design.