Sure, the Knockout offers knockout-good looks. But look beyond its awesome exterior to see what's really special. The Knockout features Kershaw's Sub-Frame Lock. What that means is that we've "knocked out" a piece of the machined aluminum frame and attached a stainless-steel plate in its place. It's this steel plate that moves behind the knife blade to lock it open safely and very securely. Yet because only part of the knife handle or frame is steel, the Knockout can maintain its fighting weight and still provide a strong frame lock. You get a knife that's big, yet lightweight enough to carry every day. The Kershaw Sub-Frame Lock is covered under US Patent 9,120,234.