General Hydroponics pH 4.01 Calibration Solution | 8oz

General Hydroponics pH 4.01 Calibration Solution | 8oz

General Hydroponics uses the highest quality reference solutions, allowing growers to calibrate many popular brands of PH meters. General Hydroponics technicians check each batch to ensure that our solutions are precisely calibrated and yield reliable readings each time they are used. This can be used to calibrate any pH meter that requires pH 4.01 solution.