Leviton® ODC and ODW series sensors provide a full line of self-contained PIR, ultrasonic (U/S) and multi-technology (M/T) occupancy sensors. The sensor's main function is to turn the lights ON or maintain the lights ON while movement is detected within the sensor's field-of-view and turn the lights OFF when the space is vacant. The PIR models use a dual element PIR heat detector that resides behind a multi-zone optical lens. This fresnel lens establishes dozens of zones of detections. In order to trigger the sensor the heat source must move from one zone to another. The U/S models utilize sensors which emit continuous reflective frequency waves. Any movement within the sensor's field-of-view will cause a shift in the original emitted frequency. The sensor identifies the change as movement and controls the light accordingly. The M/T sensors combine both PIR and U/S technology for unrivaled performance and reliability. The sensors will use PIR technology to initially turn the light ON and use the U/S technology to keep the lights ON.