Turn any mask into a high-performance antiviral mask! This mask filter, treated with Etak antiviral processing, reduces 99% of viruses and maintains its effectiveness even after 50 washes. 【Patent Pending! 安心の国産マスクフィルター (Reliable, Made-in-Japan Mask Filter)】 This high-density twill mask filter is made with antibacterial and antiviral fabric (Clenze) used in hospital bed sheets and white coats, coated to generate negative ions. It reduces over 99% of specific viruses attached to the mask surface, and through ion adsorption technology, it adsorbs nano-level specific viruses that pass through the gaps in the fibers, preventing them from entering the throat and nose. 【3 sheets for 150 days. Only 6 yen per day!】 Disposable masks and handmade masks can be quickly transformed into antibacterial masks with just one of these filters. It has passed the virus inactivation performance test after 50 washes in a household washing machine. (Test method: Compliant with ISO18184) Because it is small and does not take up much space, it is also ideal for stockpiling in case of disasters. 【Less likely to be bothered by unpleasant odors】 The cause of unpleasant odors in masks is the proliferation of bacteria. This product uses fabric that has the effect of suppressing the growth of specific bacteria, so it is less likely to be bothered by odors even after long hours of use, and a clean and comfortable state lasts longer. 【Warm in winter, cool in summer. Heat-generating and breathable Wolf Thermo】 It uses "moisture-absorbing heat generation" material, which allows the fibers themselves to generate heat and warm the body. In addition, it secures the necessary air layer within the fibers, and also exhibits the effect of releasing excess temperature in the summer. Wolf Thermo, which combines the functions of heat generation and breathability, keeps you warm in winter and cool and refreshing in summer, like animal fur. 《Product Details》 Size: L/W14×H10cm M/W12×H8cm S/W10×H7cm ※ Please comment with your desired size. Color: White (with printed patterns) Quantity: 3 sheets Material: 65% polyester, 35% cotton UV cut rate: 99.9% Quick-drying: 35.6 (Excellent) We are selling at this price because Mercari charges fees and shipping costs. It is even more affordable on our own website, Amazon, etc. https://www.trust-chemical.jp/shop Thank you for viewing.