Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Wusthof Classic Western 6 in. Chef Knife
Product description: Arguably the only knife you need, the Wusthof Classic Western 6 in. Chef Knife is perfectly balanced and the right size to fit your hand. This must-have kitchen knife is beautifully designed for the master chef and cooking enthusiast. It has a six-inch tempered high carbon steel blade that's triple-riveted to the seamless black synthetic handle. This knife is dishwasher safe, but we recommend hand washing as you would with any fine cutlery. About Wusthof Since their humble beginnings in 1814, the Wusthof family business has adhered to the same basic set of principles regarding their products. Their Trident logo is a representation of these principles, a symbol of form, function, and uncompromising quality. Today, Wusthof stands firm behind a strong line of products, including an assortment of more than 350 forged knives, as well as cutting boards, knife blocks, kitchen tools, and scissors, all of which are produced by dedicated workers at state-of-the-art facilities in Solingen, Germany. Forged from a single bar of high carbon steel. Seamless black synthetic handle triple-riveted. A well-appointed kitchen essential. Dishwasher safe. Lifetime manufacturer's warranty against workmanship defects. Blade length: 6 in..
Product feature: Forged from a single bar of high carbon steel, Seamless black synthetic handle triple-riveted, A well-appointed kitchen essential, Dishwasher safe, Lifetime manufacturer's warranty against workmanship defects
Product brand: Wsthof
Target attributes: Set Size
Answer: attribute: set size
value: None
source: None