If you're looking for a reliable leash, you should be looking at if an option is durable or not. While leather leashes are not unaffected by chewing, they are much stronger than, say, nylon. Leather dog leashes do not fray, and they can handle water and dirt much better than leashes made using other materials.
GENUINE FULL GRAIN LEATHER LEASH - for a lifetime of heavy use. Made from a single long piece of thick premium grade leather to last even through extreme
BEAUTIFUL, STRONG, AND DURABLE - Resists water & stains with minimal care, yet feels supple and won't tear at your hands or collect hair like nylon leashes when training, walking, or running with your pet.