Iconic Dr. Martens 7-eye safety boot with hard-wearing air-cushioned sole unit. An oiled, tumbled, full-grain leather. Construction: This traditional PVC work boot cleated sole is heat-sealed and benefits from a wooden shank for improved mid-foot ridgidity. It's slip-resistant with a high degree of oil and abrasion resistance and has first-class energy absorbing qualities in the heel strike area. sole Material: This is a Goodyear-welted product. The upper and sole are sewn together, not merely glued, like many footwear constructions. This, together with our Z welt-stitch and heat-sealing process, makes it unique to Dr. Martens.