Ultimate Construction: Each toy is made with two layers of industrial grade nylon, and one layer of soft fleece on the outside. All of the layers are sewn together to make one super strong layer of material. Each toy is sewn together with 2 layers of linear stitching. After the toy is sewn together an additional piece of black nylon trim is added to cover the four rows of stitching. This extra piece of nylon is sewn with 3 linear stitches to give the product a total of 7 seams! Now that’s one tough toy! Each toy is washable (air dry) and they float! (Not Recommended for extremely tough chewers. Our Ultimate series toys will work best for them.)