Cool Mesh Fabric: Made from a soft, light mesh fabric that encourages air circulation around the baby, helping to keep their body temperature cool and constant during warm nights. Transition from Swaddle: Designed to aid in transitioning from swaddling to free arms without disrupting the baby's sleep. It's safe for babies who have started to roll onto their tummy during sleep, as they can move their arms into their preferred position. Unrestricted Arm Movement: The Sleepy Hugs Original allows babies to move their arms freely while sleeping, providing security to calm their startle reflex while still allowing them to sleep comfortably. Features: Full-body length zipper with top zipper cover and a long zip along the bottom for easy middle-of-the-night nappy changes. Hip-friendly wide sack design that can easily accommodate a hip dysplasia brace, ensuring comfort and safety for babies with hip dysplasia. Optional use of a free 'Extra Hug' Belly Band/Strap for additional security, allowing caregivers to customize the sleep suit to the baby's needs. Size: Designed for babies aged 0-3 months, ensuring a proper fit for newborns and young infants. Overall, the Baby Loves Sleep Sleepy Hugs 'Cool' sleep suit offers a comfortable and safe sleep solution for babies during warm summer nights, facilitating a smooth transition from swaddling to free arms while providing essential features for convenience and customization.