This heavy Duty Utility Knife has a Retractable blade and is constructed of a heavy duty metal casing with a rubber grip around the handle. It features a quick release button to load or unload standard size utility knife blades, a rear storage compartment and it also doubles as a rope or cord cutter. It comes with 6 blades. This heavy Duty Utility Knife uses standard Utility knife blades so replacement blades can be purchased anywhere.