Stop guessing about sunlight. The BSIDE L1 Digital Light Meter gives you an exact read on what your plants are actually receiving, so you can stop moving them blindly from window to window. It measures both Lux and Foot-candles up to 200,000 Lux, making it just as useful for checking a dim bedroom corner as it is for testing a high-output grow tent LED. It is built for straightforward, everyday use. Pull off the sensor cap, turn it on, and hold it at leaf level, pointing toward the light source. The screen locks your reading with a quick press of the Hold button, and the included heavy-duty 9V battery means you can start testing your home's lighting the minute you take it out of the box.