Red Litmus Test Paper by Precision Laboratories.
Red Litmus test paper is a foolproof pH test to determine if something is a base. The Red Litmus test paper does not come with a color chart as it cannot provide you with a defined pH value. The test strip will turn blue if dipped into an alkaline solution (pH >7).

Instructions:
Remove one Red Litmus test paper from the vial, being careful not to touch the strip anywhere other than where you grasp it.
Dip the strip into the solution to be tested for 1-2 seconds and remove.
The test strip will turn blue in seconds if dipped into a solution that is a base, and will remain unchanged if not.
NOTE: The solution must be water-based.

Disclaimer: Precision Laboratories products are not approved for use as medical devices. Products and product information is for informational purposes only and not intended for use to diagnose, treat, cure or prevent any medical condition.

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