Fangrui Product Details 1. Compact Design, Easy To Use Every Day 2. User-friendly, Large Screen Display And Easy To Operate 3. Record Up To 100 Measured Values 4. For Real-time Display, It Shows The Last Four Recorded Data 5. Max / Min / Avg Data Importance Of Photo Synthetically Active Radiation (par) Meter: Photosynthetically Active Radiation (par) Refers To The Spectral Range Of Solar Radiation That Is Crucial For Photosynthesis In Plants. This Light Energy Is Absorbed By Pigments Such As Chlorophyll, Initiating The Process Of Converting Carbon Dioxide And Water Into Glucose And Oxygen. Par Meters Measure The Intensity Of Light Within This Range, Providing Valuable Information For Optimizing Plant Growth, Determining Optimal Light Levels For Indoor Cultivation, And Assessing The Effectiveness Of Artificial Lighting Systems. Hold Function. Auto Turn Off Function After 3min Of No Usage. Simple Calibration Function. With Tripod Socket. Low Battery Indicator. Specifications: Ppfd (photosynthetic Photon Flux Density) Measurement