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Amazon.com: Apogee Instruments MQ-500 Full-Spectrum Quantum PAR Meter - Digital PPFD Meter for Indoor Grow Lights, Sunlight & Plant Monitoring : Patio, Lawn & Garden
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Amazon.com: Apogee Instruments MQ-510 Underwater Full-Spectrum Quantum PAR Meter - Digital Light Meter for Aquarium Lighting & Aquarium Plant Care : Pet Supplies
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