Miles Supply offers a variety of utility knives. The first, pictured on top, has heavy duty fixed blades and an easy open hinged case design for easy blade changes and its ergonomic handle provides comfort and control. The middle retractable utility knife has a safety lock and is constructed of heavy-duty die-cast zinc, with eleven blade positions. The bottom utility knife has an interlock nose for durability and is constructed of die-cast metal. All utility knives use standard blades.