Stretching like rubber bands over the soles of shoes or boots, Yaktrax Shoe Ice Grippers provide stability and traction on both ice and snow. They are made of injection-molded plastic and feature wrap-around small metal coils in double-diamond design. As the foot goes down, the coils embed in the ice below; as weight transfers to the foot, the coils squeeze into the ice, providing stability in all directions; then as the foot lifts, the coils release, remaining snug on the shoe.