Sennheiser PMX680 Sports Earbud Headphones - Black/Yellow (Certified Refurbished) This Certified Refurbished product is tested and certified to look and work like new. The refurbishing process includes functionality testing, basic cleaning, inspection, and repackaging. The resulting product includes all relevant accessories, comes with a minimum 90-day warranty, and may arrive in a generic box. Only sellers who meet a high performance bar may offer Certified Refurbished products on Amazon.com Sweat and water resistant Neckband headphones for comfortable fit High-output drivers for energizing sound DuPont Kevlar-reinforced cable for unmatched sound