The self-retracting safety knife features a spring-loaded mechanism that automatically retracts the blade when the button is released, ensuring enhanced safety. It has built-in blade storage that can hold up to 5 blades, conveniently housed within the handle. The tool-free blade change system, with a simple thumb-screw mechanism, allows for quick and easy blade swaps without the need for extra tools. Built for durability, this heavy-duty knife boasts a full metal body, making it a reliable choice for tough jobs.