When looking at dog collars for big/large dogs, you will find that there are different size lengths, but they also come in various widths. In general, thicker or wider collars provide more support, making them ideal for large breeds. They are very comfortable to use because they reduce the extra pressure on the neck when large dogs get out of control. However, keep in mind that full collars tend to weigh more, which is why it's not a recommended option for small breeds. If you are uncertain about your dog's strength, it's best to rely on a full dog collar, especially if your dog is growing and is about to increase in size.