HALO Sleep Sack Micro Fleece Wearable Blanket Small Blue Size: Birth to 6 Months (10-18lbs) 100% Polyester HALO Sleepsack Micro-Fleece Wearable Blanket, TOG 1.0, Baby Blue, Medium The original wearable blanket replaces loose blankets in the crib for a safer environment; the #1 choice of hospital nurseries to promote safe sleep | Made from a super-soft polyester micro-fleece fabric with a TOG rating of 1.0, just the right comfort for moderate seasons or climates; can be layered with warmer sleepwear for cooler temperatures; plush inside and out and wicks away moisture | Unique, roomy sack design recognized by the International Hip Dysplasia Institute as "hip healthy" - allows room for kicking but cannot be kicked off, so Baby stays warm and safe all night | Inverted zipper opens from the bottom for easy diaper changes; sleeveless to reduce the risk of overheating; arm and neck openings sized for a safer fit | Available here in Small size designed for babies weighing between 10 and 18 pounds who are generally 0-6 months old