RANGE UP TO .5 MILESALERTS WITH LIGHT & SOUND WHEN VEHICLES OR PEDESTRIANS APPROACH PERFECT FOR HOME, BUSINESS, PROPERTY & WORKSITE EASY INSTALLATION EASY OPERATION WEATHERPROOF OUTDOOR SENSORS WITH ADJUSTABLE SENSITIVITY CONTROL EXPANDABLE UP TO 4 SENSORSIELCWA2000. CWA2000. Chamberlain CHAMBERLAIN CWA2000 Wireless Motion Alert System.