Breathable 100% Cotton Material Lemon-patterned Swaddle Perfect for All Seasons - Material: 100% Cotton - Design: Lemon Pattern - Seasons: Suitable for Spring, Summer, Autumn, and Winter - Features: Breathable Mesh - Type: Cotton Mesh Thank you for viewing. This is size S, for babies aged 0-3 months. I purchased this but my baby sleeps well and I haven't used it. The previous owner also only tried it on and then passed it on to me.