Mega Construction: Seven Layers of Material - Three Layers of 600 Denier nylon, three layers of PVC, and finally one layer of soft fleece. All seven layers are rolled together and then sewn together in a one inch cross pattern to prevent layer separation. Seven Rows Of Stitching - Each toy's seven layers of material are sewn together with two rows of linear stitching AND two rows of cross stitching. Those four rows of stitching are protected with a nylon webbing that are sewn three MORE times! Protective Webbing - Additional industrial grade nylon webbing is sewn around the outside edge with three rows of stitching to cover and protect the first four rows of stitching. Squeaker Safety - Each Squeaker is safe and quiet because they are sewn into a nylon safety pocket beneath seven other layers of materials. Each toy is washable (air dry) and they Float!