The novel transparent polyolefin, polyester or polyamide article disclosed is stabilized against the effects of light, oxygen, heat and agressive chemicals by addition of 0.005-0.30% by weight the polymeric substrate of a hydroxyphenyl triazine UV absorber, and is characterized by its thickness between 1 and 500 .mu.m. Preferred polyolefin articles thus stabilized are agricultural films containing as further stabilizer a sterically hindered amine. The novel compositions act as selective UV filter especially useful in agriculture.