The test strips are mainly made of safe and durable paper materials with a long service life. The measuring strips can be used to test the water quality of swimming pools, spas, aquariums, hot tubs, fish ponds, industrial water, etc., which helps to keep the water quality of the swimming pool or spa fresh. The dip test strips are also a good way to know if your drinking water is in a healthy and clean state. The pool test strips are also very simple for first-time users and can be carried with you. The test strips with 7-in-1 design are a quick and easy way to test water. Specification: Origin: Mainland China Model Number: Test Strips Bottle size: about 96 * 36mm/3.77 * 1.41 inch Detection range: Total hardness: 0-50-100-250-500-1000 Total bromine: 0 0.5/1 1/2.0 3/6.6 5/11 10/22 Total chlorine gas: 0-25-50-100-250-500 PH: 6.2-6.8-7.2-7.6-8.0-8.4 Total alkalinity: 0-40-80-120-180-240 Residual chlorine: 0 0.5/1 1/2.0 3/6.6 5/11 10/22 Acid cyanide: 0 30-50 100 150 240 Note: Due to different batches, there may be slight differences in the appearance of the test paper/box, which does not affect its use. Please refer to the actual item received for random shipment! Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 50/100 x Test Strips 7-in-1 Design: The test strips adopt a 7-in-1 design which is a quick and convenient method to test water quality, including pH value and chlorine level testing. User-Friendly: Our swimming pool test strips are very simple to use, even for first-time users, and can be carried with you wherever you go. Health Indicator: The immersed test strips are also a good way to know whether drinking water is in a healthy and clean state. Wide Application: The test strips can be used to detect the water quality in swimming pools, hot tubs, aquariums, fish ponds, industrial water, and other places, helping to maintain fresh water quality for your swimming pool or spa. Durable Paper Material: Our 7-in-1 swimming pool water test strips are made of safe and durable paper material, with a long service life.