SIZE CHART AND ROOM TEMP GUIDE

Size Chart. Small is for 3-6 months, 23-28" tall, 10-18 lbs. Medium is for 6-12 months, 26-31", 15-24 lbs. Large is for 12-18 months, 30-34" tall, 22-28 lbs. XL is for 18-36 months, 35-39" tall (Modern Rainbow new collection fits up to 42"), 26-38 lbs. .
.
.
Our sleep sacks come in two weights: 
Lightweight (Under .5 TOG): Designed for room temps 71*F++
Midweight (Under 1.0 TOG): Designed for room temps 68-74*F
.
Layer your sleep sack to the climate. We recommend that you select breathable fibers (like cotton or bamboo), and if the temp is on the colder side, layer footie PJs with a onesie under your sleep sack. 
.
.
.What to Wear. With our Lightweight sleep sack in a room that is 74-78°, wear a onesie; in a room that is 71-74°, wear pajamas; in a room that is 68-71°, choose a midweight sleep sack. With our midweight sleep sacks, in a room that is 74-78°, switch to a lightweight sleep sack; in a room that is 71-74°, wear a onesie; in a room that is 68-71°, wear pajamas.
.
.
NOTE
.
These are guidelines—always assess your child's PJ and wearable blanket combo to make sure they are not overheating. A key sign of overheating is sweating, with a damp nape of the neck. As a general rule, it's better for your baby to be cool than to be hot. And note—it's normal for a baby's hands and feet to be cool to the touch.
.
.
.
.
.
.