This is a pack of 3 Light Dependant Resistors (aka, Photoresistor, Light Sensor, Photo Sensor, or depending on your point of view, Dark Dependant Resistor )).
Model GL5516 (well, so the Chinese fellow said) which means that the Dark resistance should be 500k+, and the 10 Lux (Light) Resistance should be in the 5K area.
Typically you would use an LDR like this for relative approximate measurement rather than trying to convert the resistance into a direct measurement in Lux, as the variance in resistance is quite high. For example, an LDR is perfect for your security lights to know when it's night (or dark enough), but not so good for your camera to know that the ambient light is of a certain lux.
All of our products are shipped from Christchurch, New Zealand using CourierPost for NZ, and Airmail for international.
