This lens has many faces: Tokina 19-35mm f3.5-4.5, Tamron 19-35mm f3.5-4.5, Quantaray 19-35mm f3.5-4.5, Cosina 19-35mm f3.5-4.5, Phoenix 19-35mm f3.5-4.5, Vivitar 19-35mm f3.5-4.5, and possibly other brands, all based on the lens designed and made by Cosina. There may be variations in cosmetics or small design differences but the basic lens is the same.