Product Background: Free chlorine (total chlorine) includes free chlorine and combined chlorine where the free chlorine exists as hypochlorous acid ,hypochlorite ion and simple substance chlorine and combined chlorine as chloramine and  organic chloramine . Usually due to chlorination, there exists surplus chlorine in water , which not only affects the taste and odor of the water, undermine its quality , but also may  react with  some organic matters in the water, generating a series of chlorinated hydrocarbons, such as trichloromethane-bromoform, bromodichloromethane ,dichlorodibromomethane, which have teratogenic ,carcinogenic and mutagenic effects. In addition, surplus chlorine may generate chlorine gas, another toxic matter, which, when in excessive concentration , may cause damages to skin , mucosa,respiratory passage and other human organs, or even death. Hence, developing a new free chlorine testing reagent enabling fast and simplified determination is of great importance for water  quality testing and  assessment. The researchers of Ningbo Thaile Chemical Technology Co., Ltd have after years of  in-depth study , successfully developed a new free chlorine test reagent , under the brand of "Thaile". The invention of this reagent can achieve better and reliable results with greatly simplified operation and lowered testing costs.
Product Theory: Use a specific high-sensitivity reagents, it can generate chemical reaction with chlorine and show color.
Product Use: Quick test free chlorine in water. Usually it used in on-site rapid testing of living water, aquaculture, environmental protection, industrial water etc. 
Product Features: Accurate, easy to handle, inexpensive, easy to carry.
Method of Using:
1.Wash the colorimetric tube twice with water sample. Then, measure and take certain amount of water using the colorimetric tube. Adjust the level to the graduation mark of 15ml using a plastic dropper.
2.Drip 1-2 drops of Reagent into the colorimetric tube and shake up.
3.Read the free chlorine value according to the color change of the solution, against the color chart. (the value of free chlorine can be determined immediately after adding the reagent and allow 10 minutes dwelling time for total chlorine).
4. When using this reagent, the color change only occurs when the solution being tested is of pH≤7, if pH＞7, please add a few more drops.
Cautions:
1.If the water sample appear turbid, filter the sample , or stand the sample until it is clear, then take sample from the upper part, before testing.
2.Try to compare the colors in bright light.
3.The plastic dropper is used only for adjusting the water volume when measuring and taking the water, not for dripping the reagent. The above mentioned “drop” of reagent represent the drop squeezed from the reagent bottle.
4.This product is slightly irritating and aggressive, avoid inhaling. In case of body contacts, rinse with water.
5. After use, please tighten the cap to avoid ineffectiveness. 
6.This is test reagent ,not food or drink, is toxic and harmful if swallowed. Keep out of reach of children.
7. Store in a cool and shady place.
Liability: The manufacturer and its authorized reagents are free from any liabilities due to taking by accident of children and misunderstanding or misuse of the users. If result is suspected based on this test, consult an analytical testing laboratory and take the necessary precautions.
Appearance: Watery liquid.
Package of the Product: LDPE bottle.
Specifications: 10ml
Including:Reagent:4pcs；Colorimetric Tube:1pc；Plastic Dropper:1pc；Colorimetric Card:1pc；Users’Manual: 1 pc
Product standard: QB-TCS-WTR-2009
Validity: 1 year
Manufacturer: Ningbo Thaile Chemical Technology Co., Ltd
Website: http://m.8qqos3p5ki.com      http://nbtlhg.1688.com