North Mercury Vapor And Chlorine Cartridge For 5400, 5500, 7400 And 7500 Series Air Purifying Respirator (APR) With End-Of-Life-Indicator North Mercury Vapor Cartridge with ELSI is available for 5400, 5500, 7600 and 7700 Series respirators. When properly fitted these cartridges protect against Mercury Vapors. The addition of a P100 prefilter adds protetion against all particulates. Features: Cartridge is interchangeable to the 5400 Series, 5500 Series, 7600 Series and 7700 Series respirators. Color coded for quick and easy identification. Eliminates the need to inventory several different kinds of cartridges and filters. Specifications: NIOSH approved Safety Products