Coast Products DX321 and DX320 knives feature the patented double-lock safety switch giving users a second level of safety. The double-lock mechanism works in addition to the liner-lock, providing a second lock when the blade is open. Depending on the knife's design and purpose, users can choose from a variety of handle materials. The DX321 and DX320 knives feature high-carbon stainless steel blades that are sharp, tough and corrosion-resistant.