A ballpoint pen knife is a

multi-tool A multi-tool (or multitool) is a hand tool that combines several individual functions in a single unit. The smallest are credit-card or key sized units designed for carrying in a wallet or on a keyring, but others are designed to be carried ...

pocket knife A pocketknife is a knife with one or more blades that fold into the handle. They are also known as jackknives (jack-knife), folding knives, or may be referred to as a penknife, though a penknife may also be a specific kind of pocketknife. A typ ...

consisting of a blade concealed inside an ordinary-looking

ballpoint pen A ballpoint pen, also known as a biro (British English), ball pen (Hong Kong, Indian and Philippine English), or dot pen (Nepali) is a pen that dispenses ink (usually in paste form) over a metal ball at its point, i.e. over a "ball point". ...

. The blade, typically in length, is usually hidden. They first appeared as custom-made pens from various custom knife makers before being mass-produced by production companies.

Uses

Pen knives such as these are designed for

self-defense Self-defense (self-defence primarily in Commonwealth English) is a countermeasure that involves defending the health and well-being of oneself from harm. The use of the right of self-defense as a legal justification for the use of force ...

due to their ease of concealment. Their small size renders them impractical as weapons in elaborate combat, but their slim profile allows them to cause great harm in close-range combat with an element of surprise. A knife of this type can be used as a standard letter or package opener. The knife can also be used for cleaning fingernails, peeling fruit and vegetables, cutting meat, and carving or shaping wood. They come in many versions, including variants with special purpose

razor A razor is a bladed tool primarily used in the removal of body hair through the act of shaving. Kinds of razors include straight razors, safety razors, disposable razors, and electric razors. While the razor has been in existence since bef ...

s for shaving.

Kinds of blades

All ballpoint pen knives come with straight blades, which are easier to conceal than curved blades. These blades are fixed to the topmost part of the pen, hidden inside a hollow cap, serving as both the pen's end and the knife's sheath. Common blades may be the single-edged thrusting type or the double-edged

dagger A dagger is a fighting knife with a very sharp point and usually two sharp edges, typically designed or capable of being used as a thrusting or stabbing weapon.State v. Martin, 633 S.W.2d 80 (Mo. 1982): This is the dictionary or popular-use de ...

type, or even an unsharpened stiletto type point that can only thrust, not cut. Blades can be razor-sharp or deeply

serrated Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied p ...

for use in a range of situations. Swiss Army Spectrum Series released their S.A.S.S. Ballpoints, which look and function like regular ballpoint pens. They come with an array of foldaway blades and tools including knife, scissors, file, opener, screwdriver and battery-powered light.

Legality

Ballpoint pen knives, because they allow a knife to be disguised as an innocuous object, are subject to restrictions or prohibitions in some jurisdictions. For example, in North America they are not available for sale in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

References

{{Pens Pocket knives Blade weapons Pens