- Feb 01, 2018 -
It is well known that clothing in the processing of the needle will appear, of course, Waterproof series is no exception. How to ensure that these needle does not leak, so seemingly simple problems also puzzled us for thousands of years, because the ordinary tape in the water is not a touch. In the 20th century, only a handful of countries in the world use, the material is very expensive, only in the United States, the Soviet Union and other military more developed countries only appear, and its only use in space science and technology. It is technically confidential to other countries.