Unique patented wings allow natural ARMS UP™ position. ARMS UP™ allows true SELF-SOOTHING™ = more sleep • Swaddle in seconds with no breakouts. Snug fit for secure feel, warmth and comfort. • Twin zipper for easy diaper changes. • Easy care: machine wash on gentle, tumble dry on low. • 1.0 TOG fabric is ideal for moderate room temperatures between 68°F and 75°F • Certified 'hip-healthy' by the International Hip Dysplasia Institute allows recommended flexion for hips & legs. Used once!