Box-cutter knife


A box cutter knife (often called a utility knife) is a common tool used in
grocery stores and other places. Such a knife generally consists of a simple
and cheap holder, typically flat, approximately one inch wide and three to
four inches long, which can hold a standard razor blade. The user can
manually adjust how far the blade extends from the handle, so that the knife
can be used to cut the tape sealing a package without damaging the contents
of the package. When the razor blade becomes dull, it can be quickly
switched for a new one.

A similar tool is known in British English as a "Stanley knife", after one
of the first manufacturers to create this kind of implement.

Another style is one in which a handle, usually of plastic, contains a long,
segmented blade which slides out from it. As the endmost edge becomes dull,
it can be snapped off from the rest of the blade, exposing the next section
which is sharp and ready for use. When all the individual segments are used,
it is thrown away or a replacement blade is inserted.

Though such knives are not usually considered weapons, they were apparently
used in the September 11, 2001 Terrorist Attack against the United States.
See September 11, 2001 Terrorist Attack/Airport security for further
discussion. They have also been used by minor criminals in muggings, and
some schools ban their possession on school grounds.