Safer than a blanket, a sleep sack keeps little ones warm and cozy without any worries. Shoulder closures and a generous side zipper make it easy to put on. Easy enough for a beginner, you can quickly sew up a few in different fabrics for cozy naps year round. BASIC SKILLS NECESSARY Basic sewing, insert a zipper (instructions included) SIZING / FINISHED MEASUREMENTS Small (3-9 months), Medium (9-18 months), Large (18-36 months). Instructions on how to adjust sizes included.