Red SPD-SL cleats have 0, 2 or 6 degrees of float and are 100% fixed in positionGreat for sprinters, professional athletes or people who value the most efficient power transfer possible and are not prone to knee painNote: Red SPD-SL cleats require that you know your optimal cleat position precisely, and you are comfortable adjusting your cleats into that perfect position Blue SPD-SL cleats have 2 degrees of float – 1 degree in each directionShimano’s newest cleat option – a middle-ground between yellow (SM-SH11) and blue (SM-SH12) The yellow SPD-SL cleats are the most popular Shimano road cleat option and ideal for casual and performance riders. Regularly replacing cleats if you ride often will maintain proper foot stability and help keep knees pain free.