The Slice® 10503 Auto-Retractable Box Cutter takes safety to a new level with an ergonomic, protective J-hook handle and our patented safety blades. Avoid injuries with a tool that prevents you from accidentally leaving the blade exposed and keep your fingers safe with our protective handle. This knife uses 100 percent zirconium oxide blades that are non-magnetic, chemically inert, safe up to 1600 degrees Celsius, and never rust. Suitable for single- and double-walled corrugated.