The Atlas Scientific pH 4.00 Calibration Solution Pouche are designed for precise calibration of pH meters in hydroponics systems. Manufactured by Atlas Scientific, these pouches contain a solution with a pH value of 4.00, ideal for maintaining optimal acidic conditions in your garden or outdoor space. With dimensions of 8 x 6 x 4 inches and a weight of 1.26 pounds, this pouch is a convenient and reliable solution for monitoring and adjusting the pH levels in your hydroponic setup.
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