Description 12 doses . Vectra 3D for Large Dogs Over 95 lbs Vectra 3D Directions: Remove applicator from the package and make sure your dog is standing for an easy application. While holding the applicator upright, press down firmly on disk until both disks meet, piercing the seal. See illustration on the packaging. Using the tip of the applicator, part your dog's hair at the base of their tail and begin applying the product evenly in a continuous line along the spine until you reach the shoulder blades. Apply entire contents of the tube. Avoid superficial application to your dog's hair. Repeat every month or as recommended by your veterinarian.