One piece horn cover

One piece plastic molded structural unit and door knocker constr

One-way roadway marker

Open-closed indicator for a valve

Operation indicator

Opti-mechanical displacement microindicator

Optical device having light-mixing element

Optical display unit for pneumatic systems

Optical temperature indicator using thermochromic semiconductors

Ornamental vehicle identification device

Oscillating signal for bicycles

Output air supply hazard annunciator

Over inflation and under inflation indicator for tires

Over temperature alarm indication apparatus

Over-height vehicle barriers

Over-height vehicle barriers

Over-temperature indicator device for freezers

Over-temperature warning device

Overhead barrier warning system for trucks or buses

Overheated-axle indicator device