This natural flea control for dogs collar is made using a blend of Lemon eucalyptus oil, Linaloe oil, and Lavender oil to provide reliable and natural flea and tick protection for dogs.8 months of protection: Tanness' tick and flea collar for large dogs provides reliable protection up to 8 months to repel and eliminate ticks, fleas, and other critters thanks to the high concentration of natural oils so that you don’t have to worry about replacing it any time soon.