Our twice-sold-out, award-winning HALO® SleepSack® Ideal Temp is the only SleepSack with built-in temperature regulation. We've taken our existing design and enhanced it with IntelliThread™ technology, which absorbs and stores excess heat when your baby is warm and releases it back when needed. This keeps your baby at a comfortable, steady temperature throughout the night. Plus, the IntelliThread™ fibers are permanently embedded in the fabric, so they’ll never wash out or fade, making it effortless to dress your baby for sleep in any season.