PREMIUM POLYESTER/RAYON BLEND – Boasting three layers of buttery knit fabric for superior softness and stretch, our three-layer sleep bags are designed with baby’s comfort in mind. That’s why we created them with ultra-soft, breathable fabric with just the right hint of stretch. You can feel confident that baby will feel cozy and comfortable snuggled in this special sleep bag as the safest alternative to using loose blankets. These sleep bags are made from the same ultra-soft and stretchy material as our original knit swaddle blankets. WARM AND COZY – Our Sleep Bags 0-6mo and 6-12mo have a 1.25 Thermal Overall Grade (TOG) rating ideal for room temperatures between 65 – 75 degrees F and a sleeveless design to offer the perfect amount of warmth for year-round use helping baby sleep through the night. GENEROUS SIZE The 0-6 month size provides a length of 28 inches, width of 13 inches under the armpits and 18 inches at the widest section of the sleep bag.