Instruction: Extract the value of the target attribute from the given product information and output it along with the corresponding source.

Input:
Product title: Powell Monster Twin Headboard
Product description: Where ordinary youth bedroom furniture becomes extraordinary sleep, study and storage. This twin headboard only features simple contemporary rounded corner styling, a textured chrome center plate with horizontal square tube slats on either side. The heavy gauge powder coated tubular steel frame and textured chrome decorative plate give this contemporary headboard the rugged construction to survive in any youth environment. Fully assembled.
Product feature: Monster Bedroom Twin Size Headboard - overpacked, Fully assembled, 38-3/4" x 40-1/2" tall
Product brand: Powell Furniture
Target attributes: Size
Answer: attribute: size
value: twin
source: product title
attribute: size
value: twin
source: product feature
attribute: size
value: twin
source: product description