I needed storage bins to hold delicates, leggings, and knee socks/thicker winter socks in my closet's built in shelves, and these fit perfectly in the space. They also hold a surprising amount - I am storing approximately 20 - 30 pairs of leggings in one, and about 30 pairs of thick socks in another. The fabric isn't thick, and I would hesitate to store anything heavy (like toys or books), as I think the sides wouldn't hold up. But for softer items, these are great. 

Pros: Hold a good amount
Cons: Thin fabric