PH4 Solution, 220ml Milwaukee Instruments PH4 Solution, 220ml (MIMA9004)Available in 220ml bottles and 20ml sachets. Traditional buffer solutions are packed in 220ml leak-proof bottles and are recommended for lab application. Sachets are sealed against light and air and are ideal for on-the-spot calibration. Simply open, insert the tester or electrode into the sachet and calibrate. Sachets are sold in... — Ships from HF: OR, CA, CO, MI, PA USA....more info.