Yield stress not distinguishable from tensile strength.Yield.distinguishable.WeatheringGeneralMost plastic materials undergo some decay in properties andchanges in appearance during prolonged exposure to outdoorweathering. Natural and pigmented ZYTEL® nylon resinshave only moderate resistance to the effects of sunlight butspecial weather-resistant compositions retain their propertiesand appearance for years.ZYTEL® 101 in natural and colours has been used successfullyin outdoor applications. However, when exposure toultraviolet light is severe and sustained and when maximumtoughness must be retained over a period of years, weatherresistantcompositions should be used.