Full 8 hours of use per filter for all day protection 99%+ filtration efficiency Captures dust as fine as 0.3 microns at 50 litres per minute Suitable for all woodworking tasks; masonry and demolition work; fibreglass; mixing concrete; mortar and plaster; welding; hand and power sanding and many more Available as a single mask or in a pack of 5 filters and a frame assembly Reusable frame with soft rubber face seal and head straps Exhalation valve which is facing downwards to prevent glasses and googles misting Protection against airborne Coronavirus when used in conjunction with basic hygiene**