Humidity-Sensor-Kit-Pack-of-10-Rapid-PAC-2003-P-A-pack-of-components-to-build-10-humidity-sensors-ideal-for-class-projects-with-students-working-in-small-groups-P-P-This-general-purpose-circuit-detects-changes-in-humidity-&-switches-the-LED-on-or-off-accordingly-The-sensitivity-of-the-circuit-can-be-set-by-adjusting-a-potentiometer-P-Rapid-Humidity-Sensor-Kit-Pack-of-10