Sun protection is very important for animals, especially those that have cancer. The Epi-Pet Sun Protector Spray for Pets is widely recommended and is a regular choice amongst many people as it is the only FDA compliant sunscreen for dogs!
Please note that dogs with skin cancer shouldn't be exposed to the sun! For more information, please read this informative post on the Dog Cancer Blog:
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Protects from Sun Skin and coat conditioner Aroma Therapy Non-greasy and non-oily Solution Only FDA Compliant Pet Sunscreen