Wholesale collars, leashes and carriers. Handling dogs requires a specific set of products, and every dog is different in terms of what kind of collar, leash and carrier they may need. All dogs need collars to identify them, and the four most popular collars are nylon styles, which come in a variety of lengths and thicknesses to suit different sizes and breeds. With a collar or harness, the key to dealing with the problem is the leash, also known as a leash. Sizes, strengths and materials vary, so these features need to be matched to the strength and needs of the dog. We have a large wholesale inventory of dog collars, leashes and dog carriers.