Secure Your Package During Transit With Our Corrugated Shipping Boxes Available In Over 1,200 Sizes! Shipping boxes are made from strong and durable corrugated cardboard material, composed of three different sheets of container boards, fluted material in the center glued between two flat layers of paper, which ensures that the items in the box are secure and well protected. Our standard shipping boxes range in size from 4 x 4 x 4" to 48 x 40 x 36". The majority of the boxes we sell are manufactured from 32 ECT lightweight C flute corrugated material, which is the industry standard. But we also offer a variety of heavy-duty boxes for customers who require additional strength and protection. With over 1,200 sizes of corrugated boxes, we're sure to have a size that will suit your needs.