- NATURAL TREATMENT - Pickio natural collars for dogs contain only the right blend of essential oils, making this collar hypoallergenic. Plant collars for dogs are the best alternative to synthetic materials. 2. Oil collars for all dogs - From the largest: Bull Terrier and Husky to the smallest: Dachshund and Jack Russell Our dog collars are practical, if the collar is too long you can cut off the excess length. 3. LONG EXPIRATION - Pickio dog collars can help your dog 24/7 for up to 8 months. Meanwhile, essential oils will work better to provide prevention for dogs and puppies. 4. Waterproof Collars - Pickio dog collars provide water resistance to keep your pets playing in the water all day, while this basic collar can still be used as a real oil collar.