FreshGadgetz Pack of 400 PH 1-14 Test Paper Litmus Strips PH RANGE FOR TESTING - 1 to 14 SIZE: 7cm x 4.5cm HOW TO USING - according the acidity of a object to test its PH value. To read the PH value by matching with the PH scale color within around 15 seconds. FUNCTION - they are perfectly used for a classroom or youngsters doing experiments and working with acids and bases. Great for teaching your kids to check PH before learning about acid-base reactions. SUITABLE FOR - pH test strips for urine, saliva, amniotic fluid, drinking water, pool, hot tub, hydroponics, aquariums, food, coffee, potassium hydroxide, and many more TOTAL: 400 Strips THE SCALE READS - from 1 to 14: 1 - 3 indicates a very acidic substance 4 - 6 indicates an acidic substance 7 indicates neutral 8 - 11 indicates alkalinity 12 - 14 indicates a very high level of alkalinity.