7.0 Quart Modular Stacking Box by Iris &reg; Durable polypropylene plastic construction. Transparent plastic keeps organized items visible and easy to locate. Sturdy snap down lid helps secure contents inside and allows for convenient space saving stacking of multiple boxes. Great solution for organizing toys in the classroom tools and parts on storage shelves in the garage or footwear and clothing accessories in a closet. Also stacks on the Large Stacking Box and the Small and Medium boxes.