NOW Foods Nature's Shield Oil Blend is an antimicrobial-focused essential oil blend inspired by the legendary Thieves Oil tradition — a combination of clove, lemon, cinnamon, eucalyptus, and rosemary essential oils that were historically associated with protection against airborne pathogens. Each of the individual oils in this blend has demonstrated potent antimicrobial properties in laboratory research, and their combination creates a synergistic effect with broad-spectrum antimicrobial activity. Diffuse Nature's Shield during cold and flu season to help purify indoor air and create a protective atmosphere. It can also be used in DIY natural cleaning sprays and surface treatments. NOW Foods blends from 100% pure essential oils, all GC/MS tested for identity and purity. Dilute heavily in carrier oil for any topical use. Not for internal use.