Well suited for those who want NIOSHs highest rated filtration efficiency in a maintenance free respirator. It provides a minimum filter efficiency of 99.97% against non-oil based particles. This respirator is an excellent choice for lead abatement, pharmaceutical manufacturing, welding, metal pouring and work involving OSHA substance specific particle exposures in concentrations up to 10 x the OSHA PEL, excluding asbestos. It features the 3M