Buff Filter Adjustable Face Mask in Makrana Sky Blue | One Size The new Buff Filter Face Mask has become an essential accessory for daily activities like grocery shopping, using public transport or going for a run. The BUFF® Filter Mask features a 3-layer, replaceable filter system in a washable mask design made from CoolNet UV+® fabric. Reliable and comfortable, featuring 98% bacterial filtration efficiency. Filters meet surgical mask standards. Features Reusable mask featuring 98% bacterial filtration efficiency. Filters meet surgical mask standards. Filters included! Each mask comes with five replacement filters. Enjoy comfort in style.