High quality Baby / Toddler Sleep Sack - Hot selling product from professional sleep consultant company, Upchild.Sg - Customised sizing that fits 18 months to 4 years old (Up to height of 1.1m) and local weather conditions in Singapore - Soft, breathable material that allows baby to sleep comfortably and soundly 1) Clouds Design - 0.5 TOG thickness - 4 Layer Bamboo Fibre - Two way zipper 2) Forest Design - 1.0 TOG thickness - 100% Cotton - One way zipper 3) Jungle Design - 0.6 TOG thickness - Four layer soft muslin - Two way zipper 4) Unicorn Design - 0.6 TOG thickness - Four layer soft muslin - 2 way zipper Using a sleep sack is a useful cue that it's time to sleep for babies and toddlers. It also keeps your child snug and prevents them from getting cold and jumping or climbing out of the cot. It's also recommended from a safe sleep perspective, loose sheets and blankets don't cover their head.