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: 16 Inch Foil Mylar Balloons Bouquet for Wall Decoration (Premium Quality, Air-Fill Only), Glossy Silver, Letters HAPPY
Product description: Form your name or event slogan with our Jumbo size 16 inches Glossy Silver Alphabet Balloon. Self sealing, premium quality balloon that is perfect for all party occasion! Decorate with foil or latex balloons to form a fantastic party centerpiece that is memorable for years to come!
Product feature: Size: 16" each letter, Easily hung on strings from ceilings or attached to wall with tape, Easy to inflate using the a straw or an air handheld pump, Reusable. Self-sealing valve for easy inflation and deflation., WARNING: CHOKING HAZARD - Children under 8 yrs. Can choke or suffocate on uninflated or broken balloons. Adult supervision required. Keep uninflated balloons from children. Discard broken balloons at once.
Product brand: Balloon Red
Target attributes: Quantity
Answer: attribute: quantity
value: None
source: None