Lot of four sleep sacks. 3 in size 6-12m all 100% cotton (Mama Cheetah 0.5 TOG & Halo I think 0.5 TOG). 1 in size 18-24m 100% cotton sack with polyester filling (Yoofoos 2.0 TOG). The lighter sleep slacks are great for spring and summer. The warmer great for fall and winter. We loved these. Some wear. Bundle 3 or more items and save 25%.