When purchasing a angle valve, it is preferred to choose an all-copper angle valve, and check the test report; in the case of sufficient light, you can put the angle valve in your hand and observe it. The surface should be as bright as a mirror, without any oxidation spots, without There are no burrs or sand when you touch it; when you touch the faucet with your fingers, the fingerprints will quickly disperse and it is not easy to attach scale. When purchasing plumbing and sanitary products, you should pay attention to asking for a product quality report and issue a detailed bill.
