Please see the following information in regard to sizing the right toys for your dog. There are three sizes in the K9 Connectables range. Broadly speaking mini toys are aimed at dogs under 10KG, medium toys are aimed at dogs 8KG – 35KG and the large toys aimed at dogs 25-45KG. If your dog is very high energy, enthusiastic and food motivated it is probably best to get a size up. Below is an image comparing each size to a standard tennis ball so you can gauge in comparison to your own dog and a tennis ball. Please also see our product image galleries for examples of different dogs playing with K9 Connectables.