... Opposing polarity protetive Features and benefits1.Made of top famous LED source Cree/Osram, high efficacy, long l ifespan, maintenance ... and corrosion, IP68.3.High quality tempered glass with excellent light transmittance.4.Comply with Ex, ib, IIC, T4, IEC60079-11, ... petroleum and petrochemical, aircraft, mi l itary, outdoors, indoors, portable-emergency kits.Working temperature: -20°C to +40°C