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: 10k Yellow Gold Round Channel-set Natural Diamond Mens Masculine Wedding Band Sizes .08 Cttw
Product description: This men's wedding band is crafted from polished 10kt yellow gold and has a simple 5mm design. Seven channel-set, natural diamonds are set across the center of the band for a simple accent. This band has a hollow underside for a lightweight wearing experience.
Product feature: .08 Ct.t.w., 10kt Yellow Gold, I2-I3 clarity; J-K color, Widest point width: 4 mm (.16 inches ) - Width of shank: 2 mm --- 1.96 grams (approx.), 1 year lost-stone and defect warranty on all products, personalized Certificate of Authenticity, gift box and free shipping included. Buy with confidence., ASIN: B00EXBMNOI, Item model number: 15685-10.5, Date first listed on Amazon: September 1, 2013, Average Customer Review: 5.0 out of 5 stars 1 customer review
Product brand: USA Diamond Center
Target attributes: Silhouette
Answer: attribute: silhouette
value: wedding band
source: product title
attribute: silhouette
value: band
source: product description