The 3M 4251 Maintenance Free Respirator is a lightweight ready-to-use half mask designed for effective and comfortable protection against respiratory hazards.The 3M 4251 Maintenance Free Respirator is a lightweight ready-to-use half mask designed for effective and comfortable protection against respiratory hazards.This half mask requires no parts assembly or maintenance and is designed for protection against organic vapours and particulate hazards.This is for up to 10 x Workplace Exposure Limit (or 1000ppm whichever is lower).It features two large bonded carbon filters for low breathing resistance and soft non-allergenic face piece material with textured face seal.This 4251 reusable half mask has been designed with a low profile to allow a better peripheral vision it has an adjustable head cradle and easy to fasten neck straps.To improve comfort the exhalation valve has been centrally positioned which allows for an effective removal of heat and moisture.These respirators can be reused until damaged the particulate filters become clogged the gas filters become saturated or after one month.FeaturesReady to use requires no assemblyProtects against organic vapours inorganic/acid gases & particulatesLightweight and comfortableAllows for good peripheral visionAdjustable head cradle and easy to fasten neck strapsSoft non-allergenic material with a textured face sealCentrally positioned exhalation valve