Size Medium (13-19lbs, up to 27 inches). Love to Dream Transitional Swaddle Sack with zip off arms. Great for transitioning baby from a traditional swaddle to a sleep sack. It gives just the right amount of snugness for baby to sleep all night long! I have 4 of the same. One for $15, 2 for $27, 3 for $40, or all 4 for $50. They retail for $35 each.