The SPD-SL shoe has three holes in the outsole to which the Road Bike Shimano SH11 Clip-on Cleats can be screwed. The triangular holes are well spaced apart. The spike is also triangular in shape and made of durable thermoplastic or composite. With the help of screws and spacer washers, it is screwed to the shoe. Washers with oval holes allow for a more precise adjustment of the cleat on the sole within a fairly wide range. It should be noted that the Bicycle Racing Shoes are very uncomfortable to walk on. Some cleat models have a special rubber pad that helps when walking. Red Road Bike Shimano SH11 Clip-on Cleats - The stiffest fixed position cleats for maximum power transfer and circular pedaling efficiency. Used by advanced athletes. The cleat in the pedal has no backlash or free play. They give the most rigid contact, the cyclist's foot does not move. Yellow Road Bike Shimano SH11 Clip-on Cleats - 6-degree leg shift for comfort. Ideal for beginners. The foot may move while pedaling.