Round Leather Collar in sizes for Toy Breeds through Large Breeds. Toy Breed and Small and Medium Dog sizes (1/2, 5/8, and 1 inch sizes) are constructed with a buckle-end style while Large Dog sizes (1-1/4 inch sizes) are made in the extended d-end pattern for extra strength. All of our round (sometimes referred to as rolled) leather dog collars have beveled and hand polished edges for comfort.