The SM-SH12 is a recent invention by Shimano and joins the features of the red and yellow cleats. The pros asked for a cleat with which the heel could still move a little, but it still had to feel as locked in as with the red ones. The round blue edge secures the shoe like with the red system, but still allows for 1 degree of play at your heel. In short: nice and tightly locked in, but easier on the knees because of the minimal amount of play.

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