We can guarantee you that nothing fits a Shimano cleat like a Shimano cleat cover. The fit is perfect, so there is no slippage.
The ribbed and molded tabs at the end of the covers make putting them on and removing them is an easy process. The durameter of the rubber is firm enough, so they do not wear too quickly, but soft enough to offer plenty of grip and traction while walking around. Shimano took the time and effort to mold a tread pattern similar to a tire on the bottom of the cleat for added traction. They are sold in pairs and fit all incarnations of the SPD-SL pedal.