(under the class definition) Apparatus having signals, indicators, registers, recorders, gauges or display devices for indicating a condition or performing a measuring function, such devices consisting of relatively movable, changeable or audible information giving parts, or having means permitting inspection of the contents of the system.
SEE OR SEARCH THIS CLASS, SUBCLASS:
83, for devices for testing or weighing the receiver contents.
SEE OR SEARCH CLASS
53, Package Making,
507+, for packaging apparatus having alarms, signals, indicators, inspection means or counters. 137, Fluid Handling,
551+, for fluid handling systems with indicator, register, recorder, alarms or inspection means.
23+, for dispensers with recorder, register, indicator, signal or exhibitor, subclasses 54+ for dispensers having inspection means. See the search notes to subclass 23 and 154 of that class.
340, Communications: Electrical,
500+, for electrical automatic condition responsive indicating system.