Today, the modern military force may need more than one version of the same piece of equipment to satisfy different field requirements. In the case of the seemingly simple knife, as many as four knives may be issued to a single force - each with its own purpose. A standard issue stainless steel scuba knife, for example, would not be suitable for use in operations where non magnetic properties are required.

The Multi Purpose Knife, as the name would imply, is designed to serve in a variety of missions. Titanium was selected for the blade based on the unique combination of properties inherent to the metal. The result is a light weight, non magnetic, non corrosive, and multi functional knife.

Experience with titanium in knife making is recent by historical standards, having occurred only in the past fifteen to twenty years. Much of this has been for knife handles, which are lightweight and often anodized to produce an array of colors. Commercially pure grades are used as they are lower in cost, relatively soft, and easy to machine. More vivid colors can be achieved with the alloy grades, but the cost is higher and they are more difficult to machine. A few manufacturers have made blades from the Ti-6Al-4V alloy. This grade is readily available, moderate in cost, and grinds and machines reasonably well. It would be the alloy of choice except for low hardness. Nitinol, an alloy containing almost equal amounts of titanium and nickel, has been used experimentally for dive knives. It has the corrosion resistant properties of titanium, and can be heat treated to a hardness in the range of steel. Extremely high cost has restricted its use for cutlery applications.

The MPK is made from a high strength beta titanium alloy which has the disadvantage of being difficult to grind and machine, and higher in cost when compared to Ti-6Al-4V. Wear resistance, however, is superior and the alloy can be hardened to Rc 44-46 while maintaining usable ductility. At this level, edge retention is good. Furthermore, corrosion will not dull the edge.

The MPK handle is injection molded in one piece, over a full length tang, and is textured and grooved for superior gripping. The handle is made from a high toughness Hytrel reinforced with the ballistic fiber Kevlar (Hytrel and Kevlar are registered trademarks of DU PONT.). It is resistant to the effects of heat and most oils, fuels, and solvents. A metal guard and butt cap are not used. This ensures the handle is electrically insulated from the blade.

The titanium alloy used for the MPK is heat treated to a range of Rc 45-47. At this hardness, resistance to abrasion is exceptional. This will be demonstrated when the edge is resharpened. Mission Knives has found that a diamond coated round sharpener works best for this purpose. The MPK will not corrode or dull under any conditions in sea water, making it ideal for a high use knife in that environment. Extended field tests have substantiated that the V-ground blade has a durable edge which is not susceptible to wear or chipping. The rounded serrations are superior for cutting a variety of materials.

Hytrel is also the material of choice for the sheath. Kevlar is added to offer the best combination of toughness, hardness and low noise signature. The sheath is designed for a close fit to the blade, preventing movement of the knife and eliminating a potential noise source.

The sheath is designed to be worn on either side of the hip on a military utility web belt. Since the MPK will be used on various utility belts, it is also configured for ease of installation without having to disturb other items. Two pairs of tie-down slots were recently added to convert the sheath into a load bearing unit. Optional ballistic nylon carrying pouches can be strapped and secured onto the sheath by running velcro straps through these tie-down slots.

Securing the knife to the sheath case is accomplished by using a nylon strap and/or a rubber hold down tab. While divers often prefer the ease of using a hold down tab, a more secure attachment may be required for some operations. The nylon strap fastens the MPK in these situations.

Sport divers often wear their knives on the inside of their calf using leg straps. This option is available with the MPK. The upper strap is strung through the jump master slots and the lower strap through slots provided on the back of the sheath. A lanyard can be strung through the bottom drain port and used as an alternative to the lower strap.