The Ultimate bone is a wonderful toy for those dogs that like to play tug or whip their toys back and forth. This toy will entertain one or multiple dogs for hours. -- soft edges won"t hurt gums. Also floats. Ultimate Construction: Each toy is made with 4 layers. 2 layers are made of industrial grade luggage material, 1 layer of plastic coating, and the other layer is made of soft fleece on the outside. All of these layers are sewn together to make one super strong layer of material. Each toy is sewn together with 2 layers of cross stitching and then 2 layers of linear stitching. After the toy is sewn together an additional piece of black trim is added to cover the four rows of stitching. This extra piece of black trim is sewn with 3 linear stitches to give the product a total of 7 seams. These toys are machine washable (air dry) and float.