Personalized Funny Mountain Biking Quote for Biker Newborn Layette. Humorous mountain biker slogan for a laugh says is my mountain bike okay. 100% combed ringspun cotton 5.8 ounce 1×1 baby rib sleeper. 3/8" flatlock binding at envelope neck and cuffs. Back sleeve flap to protect hands. Elastic opening at bottom. Infant: 0-3 Months