Riku Mask is known as Antiviral facemask, Virus resistance fackmask. It’s high quality facemask which is made with high filtration material and applied a Japan made nano grade material which has been tested with many different kind of viruses in the past 10 years, it’s the first facemask that tested with live virus in the lab in our world. Please check lab test datas for your reference. It’s known as Antiviral facemask, Virus resistance fackmask.