Nexgard Spectra Dog Yellow 3.6-7.5kg 6pk is just one monthly chew for protection against fleas, ticks, mites, heartworm and worms. It rapidly kills fleas, treats and controls ticks, mange, mites, roundworm, hookworm, whipworm and mites, and it prevents heartworm disease. Protection is available from 8 weeks of age and 2kg body weight.