The Dalric Special Cuff has a thick sole for nailing instead of rivet attachment. They can be attached to the black wedge set (see below) to make the old style Ultimates. Reasons for use: When nails fail Easy to apply Attaches to the shoe of your choice Safe, light and secure Your imagination is its limitation Recommended for Racing... a great alternative! Dr. Redden's advice is to use Equilox when the cuff fails to fit snug.