100% Natural, made of premium luxuriously-soft hypo-allergenic Australian Merino wool; GOTS certified organic cotton outer. Machine-washable. Optimal weight Merino lining so it can be used in all 4 seasons. Available in two sizes: 6-18, 18-36 months and 3-4T. Foot openings allow for mobility when child is awake. Generous size so child can tuck feet in when sleeping. Unzips from bottom for easy diaper changes. Premium quality product backed by the industry-leading One Year Warranty from a US company with US customer service. Buy with confidence from Woolino, the makers of the #1 selling and #1 rated Merino wool baby sleep bag in USA and Canada since 2010. Are you worried about which weight baby sleep bag to use and whether your baby will be too hot or cold while sleeping? With Woolino there is no need to worry because the exceptionally breathable Merino wool naturally regulates baby's body temperature to ensure s/he sleeps comfortably through the night. This luxurious baby sleeping bag will also save you buying lots of other brand sleep sack TOG ratings because it can be used year-round. With Woolino wearable blanket your child will have an amazingly comfortable sleep, which will give you a peace of mind and a good night sleep as well. • 100% Natural: SILKY-SOFT Australian Merino wool lining & organic cotton outer • Can be used in all 4 seasons - suitable for room temp. 63-77F (17-25C) • Unlike any other fiber, Merino REGULATES BODY TEMPERATURE keeping baby warm when it's cold and cool when it's hot • Openings for feet allow for mobility when child is awake• Zipper-pull guards to protect child's skin• Generous size so child can tuck feet in when sleeping • MACHINE WASHABLE and can be tumble tried on low• Nursery thermometer with dressing guide included • Meets all US CPSC children safety requirements • Woolmark certified Merino. GOTS certified organic cotton. All the fabrics and accessories are OEKO-Tex 100 certified Why Merino? A study done by University of Sydney, Australia has found that a better night's sleep is achieved when sleeping in or under wool. Significantly finer than other types of wool, Merino is the perfect fiber to have next to child's sensitive skin. It breathes, regulates temperature, manages moisture, it is hypoallergenic, easy to care for, and durable. It is naturally perfect.