Shell 100% Cotton, Filling 100% Polyester Imported The Ultimate Winter Hug: This 2.5 TOG sleeveless sleep sack acts as a thermal shield for cold nights. Our warm infant sleepwear mimics a luxury duvet, ensuring deep sleep in rooms as cool as 64°F. A winter nursery essential for newborns. Premium Cotton & Soft Quilting: Featuring a soft cotton sleep sack shell, the interior is lightly quilted for warmth without bulk. This baby sleeping sack offers superior breathability compared to synthetic fleece sleepers. Patented Shoulder Snaps: Unique snap openings simplify dressing without arm threading. Lay infants inside the nest, close shoulder snaps, then move directly to the crib for smoother nighttime transitions. Quick Diaper Change Zipper: Designed for convenience, the Sleep Nest features a high-quality inverted bottom zipper. Quickly change diapers without fully unwrapping your infant, keeping their chest warm and undisturbed all night long for a faster return to sleep. Sizing for Every Stage: Replace loose quilts with this toddler sleep sack to prevent kicked-off covers. Available in gender-neutral colors for baby boy or baby girl, with sizes ranging from 0-6M, 6-18M and 18-36M.