Here is the clinical reality: an infant's neurological system cannot effectively regulate core body temperature. Putting your baby in a synthetic polyester fleece traps ambient heat, forcing them into a dangerous "cold sweat" loop. They overheat, sweat heavily, and wake up screaming because they are damp and freezing. If you are battling false starts and warm summer nurseries, our collection of baby sleep sacks eliminates the guesswork. Engineered specifically for hot rooms (74–78°F), this 0.5 TOG sleep sack delivers the necessary tactile security of a baby sleeping bag while strictly preventing thermal failure.