KNIFE UTILITY METAL RETRACTRACTABLE. KNIFE UTILITY METAL RETRACTRACTABLE. This US-made retractable knife is designed with a lightweight yet robust aluminum blade that is ideal for quick, hassle-free replacement. This blade does not slide and can be adjusted in up to 3 positions. Offering comfort and control as it has an ergonomic blade retraction mechanism. Which, in turn, has a locking knob that holds the blade in place. The knife body includes storage for 3 spare blades.