Hi-Craft HC177 Flexible Gunite Spiked Shoes, Grey Steel spikes release air bubbles from epoxy and gunite overlays, while protecting these materials from footprints Strong3/4 inch steel spikes positioned to distribute weight across shoe Flexible plastic create comfortable movements Back stop of shoe prevents work boots from moving around on the shoe Plastic clasps on adjustable nylon straps provide a comfortable fit to secure the spiked shoe to boot