This bike cap is adjustable with a strap and button on the back. It is perfect for your baby boy to wear on a spring or autumn day. And it looks great on girls, too! This pattern includes 4 sizes (Baby to preteen) and applique bike : (Circumference, approx.): 17-18" / 44-46cm (3-6 mon), 18-19"/ 46-49 cm (6-12 mon), 19-20"/49-51cm (12-24 mon), 20-21" /51-54 cm (Preteen) Material: Worsted yarn Hook: 4.25 mm /US G One button Sewing needle Skill level: Intermediate It is easy and quick to crochet! I added lots of step-by-step photos and tutorial videos to help you to work through project. More pattern in my pattern shops: http://www.ravelry.com/designers/cathy-ren https://www.etsy.com/shop/CathyrenDesigns This pattern is copyrighted. You may not rewrite, resell, trade. No mass production allowed.