Free Bromine Range: 0~22. WORKING PRINCIPLE: PH test strip is suitable for detecting human pH value through urine and saliva, easy to operate. In the test process, tear off a small piece of the test page, use a glass rod, cotton swab or other incisive object to pick up a small amount of the object to be tested, drop on the test page, see the color change, and then compare the corresponding color classification on the color plate, you can know the PH value.
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