TREX 6326 Spikeless Traction Devices for boots and shoes reduce the risk of slips and injuries for spike-free traction on slick surfaces, particularly oil, grease and water. Powered by Soles by Michelin (SBM), they are designed for indoor work environments where extra traction is needed. To achieve superior traction, the soles are constructed with extreme rubber specifically engineered for adherence and adaptability on slippery surfaces. Tread pattern is designed to provide constant contact with slippery surfaces. Device is tested to remain flexible in temperatures as low as negative 40 degrees Fahrenheit for the sling and negative 20 degrees Fahrenheit for sole. Slip-on, one-piece slings will fit over any style of boot or shoe for added traction. Adjustable cord cinches tight for a secure fit. Heel tab allows easy on/off. Medium size fits U.S. men's shoe sizes 8.5 to 10, women's shoes 10.5 to 12, men's work boots from 7.5 to 9 and women's work boots 9.5 to 11.