TPU/PU Toughsider sole Fully lined OrthoTec PU innersole ZipSider Style Premium quality leather uppers Not everyone requires a steel toe-cap. So Mongrel has provided a number of styles featuring all the best of SP design and comfort without the metal cap. The range includes everything from riding boots to classic elastic sided designs. Including the OrthoTec Air innersole and with sole constructions and materials to match the design - they're suitable for executives to landowners and a whole range of workers in between.