The filter is 2 stages and is the same as the one introduced by Primato, the premium UFC 0.01. However, Primato recently changed it and now theirs is a 4-stage filter with manufacturing country in Korea. It is one of the few ultrafiltration filters available.
Its permeability is 0.01 microns, which is so narrow and traps almost everything from harmful elements in the water. However, it is not so small as to retain natural minerals and water trace elements, so the water remains nutritious and unaltered. Ultrafiltration technology is one of the best methods of mechanical filtration. It has 10-micron carbon on the outside to retain chlorine, heavy metals such as lead, cysts, cryptosporidia, sediment, sludge, etc. And inside it has hollow fiber membranes where the barbaric filtration takes place, cleaning the water from microbes, and various microorganisms, capable of retaining viruses as well. To understand how small the pore size of the fibers' filtration is, just think that a hair strand has a thickness of 100 microns and this filter has a pore size of 0.01.
And according to the WQA, bacteria range from 1 to 0.2 microns, which means that the filter easily retains them. Also, to understand better, the Hepatitis B virus has a size of 0.04 microns, which means it is larger than the 0.01 of the filter, so it does not pass through. I have been trusting this specific filter for a year now and I will probably choose it again. Also, the carbon used by the manufacturing company is NSF 42 certified.

The manufacturing company is Siam Cast Nylons in Thailand. And their website is carbonblocks.com, which is the same company that produces the Pure filter series.
Lastly, for informational purposes, for those who purchase it and want to know more. I also sent an email to the Asian company Siam Cast Nylon-Pure to send me the filter's certifications and test prices, and they sent them to me after about ten days. So go ahead and make your purchase without fear. It's worth it.