1. The hand held PAR meter mainly used for agriculture, forestry and other research and production departments for PAR radiation measurement. 2. It is designed to measure PAR (Photosynthetically Active Radiation) flux in wavelengths ranging from 400 to 700 nanometer.Its characteristics are the spectral response simulation probe photosynthetic function effectively, digital show, portable compact,with good accuracy and stability. 3. In controlled environment agriculture (CEA), it is ideal for growers to measure light to avoid the risk of wasting energy or damaging their plants. Operating Temperature:32°F to 122°F (0°C to 50°C) Storage Temperature:-4°F to 140°F (-20°C to 60°C) Operating & Storage:RH 0-95%, non-condensing PPFD Measurement Repeatability: +/-1 μmol/m²/sec Measurement Range :0-3999 μmol/m²/sec Display Resolution: 0.1 μmol/m²/sec (0-999); 1 μmol/m²/sec (1000-3999) Cut-On Wavelength: 400+/-10nm Cut-Off Wavelength: 700+/-10nm Power Requirements:2 x AAA batteries(not included) Colour:Black&White Material:Plastic Package Contents: 1 x host 1 x probe 2 x connections Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.