1. Category: injection molding 2.Size: 33 yards -47 yards 3. Function: anti-impact, anti-puncture, anti-static electric insulation, high temperature, oil, acid and alkali resistance (optional) 4. Inner: high quality black bubble mesh 5. Insole: EVA absorbs sweat and breathes 6. Medium bottom: opaque black nonwoven fabric 7. Large bottom: dual density polyurethane injection molded PU large bottom 8. Features: anti-skid and wear-resistant, suitable for oilfield chemical metallurgy, strong and durable