lever pack n. a set of lever tumblers
lever tumbler n. a flat, spring-loaded tumbler
which usually pivots on a post. It contains a gate
which must be aligned with a fence to allow
movement of the bolt.
loading tool n. a tool which aids installation
of cylinder components into the cylinder shell
lock n. any device which prevents access or use
by requiring special knowledge or equipment
lock service package n. a kit offered by the
manufacturer or distributor of a product, which
contains what he deems required to properly service
the product
locker lock n. a cabinet lock designed specifically for
use on lockers
lockout n. any situation in which the normal
operation of a lock or cylinder is prevented
lockout key n. a key made in two pieces. One piece
is trapped in the keyway by the tumblers when
inserted and blocks entry of any regular key.
The second piece is used to remove the first piece.
locksmith n. a person with the knowledge and
ability to select, install, service and bypass all the
components of an electrical or mechanical lock
-M-
MACS abb. maximum adjacent cut specification
manipulation key n. any key other than a correct
key which can be variably positioned and/or
manipulated in a keyway to operate a lock or cylinder
master disc n. a special disc tumbler with multiple
gates to receive a sidebar, see also “master pin”
definition 1, see also “stepped tumbler”.
master key n. a key which operates all the master
keyed locks or cylinders in a group, each lock or
cylinder usually operated by its own change key
v. to combinate a group of locks or cylinders such
that each is operated by its own change key as well
as by a master key for the entire group
master key changes n. the number of different
usable change keys available under a given master key
master key system n. 1. any keying arrangement
which has two or more levels of keying 2. a keying
arrangement which has exactly two levels of keying
master keyed adj. of or pertaining to a cylinder or
group of cylinders which are or are to be combinated
so that all may be operated by their own change
key(s) and by additional key(s) known as master
key(s)
master keyed only adj. of or pertaining to a lock
or cylinder which is or is to be combinated only to
a master key
master lever n. a lever tumbler which can align some
or all other levers in its lock so that their gates are at
the fence. It is typically used in locker locks.
master pin n. 1. usually a cylindrical shaped
tumbler, flat on both ends, placed between the top
and bottom pin to create an additional shear line
2. a pin tumbler with multiple gates to accept
a sidebar
master wafer n. a ward used in certain binary type
disc tumbler key-in-knob locks, see also “master pin”
definition 1, see also “stepped tumbler”
matrix format master keying n. a method of
generating combinations and assigning key symbols
in a master key system through the use of a matrix
maximum adjacent cut specification n. the
maximum allowable difference between adjacent
cut depths
meter lock n. 1. a padlock whose shackle consists
of a single removable post, designed for locking
utility meters or valves. 2. any of several small
devices specifically designed to lock utility meters
or valves and which require either a key or special
wrench for removal.
mis-cut adj. of or pertaining to a key which has
been cut incorrectly n. a mis-cut key
MK abb. master key
MK'd abb. master keyed
MK'd only abb. master keyed only
mogul cylinder n. a very large pin tumbler cylinder
whose pins, springs, key, etc. are also proportionally
increased in size. It is frequently used in prison locks.
mortise cylinder n. a threaded cylinder typically
used in mortise locks of American manufacture
multi-section key blank n. a key section which
enters more than one, but not all keyways in
a multiplex key system
multiple gating n. a means of master keying by
providing a tumbler with more than one gate
multiplex key blank n. any key blank which is part
of a multiplex key system
multiplex key system n. 1. a series of different key
sections which may be used to expand a master key
system by repeating bittings on additional key
sections. The keys of one key section will not enter
the keyway of another key section. This type of
system always includes another key section which
will enter more than one, or all of the keyways.
2. a keying system which uses such keyways and
key sections
mushroom pin n. a pin tumbler, usually a top pin,
which resembles a mushroom. It is typically used to
increase pick resistance
-N-
NCK sym. symbol for "no change key," primarily
used in hardware schedules
neck (of a key) n. 1. the portion of a bit key
between the shoulder and the bit(s) 2. the portion
of a cylinder key between the shoulder and the bow
negative locking n. locking achieved solely by
spring pressure or gravity which prevents a key cut
too deeply from operating a lock or cylinder
NKR abb. non key retaining
NMK sym. symbol which means "not master keyed"
and is suffixed in parentheses to the regular key
symbol. It indicates that the cylinder is not to be
operated by the master key(s) specified in the regular
key symbol; e.g., AB6(NMK).
non-fail safe adj. a feature of a security device
designed to remain engaged, for security purposes,
during a power loss
non key retaining adj. of or pertaining to a lock
whose key can be removed in both the looked and
unlocked positions
non-original key blank n. any key blank other than
an original
non removable key adj. a key which has one
or more cuts on it which trap the key in the lock
upon insertion
nose n. the part of a non-cylinder lock which
contains the keyway and rotates within a horn
NRK abb. non removable key
NRP abb. non removable pin
-O-
odometer method n. a means of progressing key
bittings using a progression sequence of right to left.
one bitted adj. of or pertaining to a cylinder which
is or is to be combinated to keys cut to the
manufacturer's reference number one bitting
one column progression n. a process wherein key
bittings are obtained by using the cut possibilities
in one column of the key bitting array
one pin master key n. a master key for all
combinations obtained by progressing only one
bitting position
open gated adj. pertaining to a lever tumbler whose
gate is in the edge of the tumbler
opening index n. the index or mark to which a
combination is dialed in order to effect an opening
operating key n. any key which will properly
operate a lock or cylinder to lock or unlock the lock
mechanism and is not a control key or reset key,
see also “change key”
Terminology
26
