|
US3295833A
|
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Protective enclosure
|
|
US3174003A
|
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Lock alarm switch with keyway adapted to receive two keys of different lengths
|
|
US3054869A
|
|
Alarm switch
|
|
US3091760A
|
|
Burglar alarm actuator
|
|
US2992420A
|
|
Capacity type burglar alarm systems
|
|
US2877361A
|
|
Burglar alarm system
|
|
US2779935A
|
|
Noise actuated disabling unit
|
|
US2749537A
|
|
Device for detecting motion in a confined space
|
|
US2779936A
|
|
Supervisory unit for burglar alarm system
|
|
US2874376A
|
|
Local alarm circuit for burglar alarm systems
|
|
US2783462A
|
|
Electrical protective burglar alarm system
|
|
US2760018A
|
|
Circuit makers and breakers
|
|
US2741675A
|
|
Vibration detecting device
|
|
US2747177A
|
|
Burglar alarm system for a movable closure
|
|
US2651773A
|
|
Ground potential compensator
|
|
US2351319A
|
|
Stylus operating means
|
|
US2129261A
|
|
Burglar alarm system
|
|
US2083335A
|
|
Electric protective system
|
|
US1919007A
|
|
Signaling system
|
|
US1881832A
|
|
Alarm system
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