A combination of Grape Seed Meal, Distiller Grains, Diatomaceous Earth, Garlic Powder, and Thiamine ?B-1. Garlic and Thiamine B-1 contain sulphur compounds. Typically insects are very sensitive to the sulphur odor, even at levels undetectable to humans. The medicinal effects of garlic have been well known for centuries and several studies from the early 90’s have shown benefits of garlic to be antimicrobial, anti-carcinogenic, improving respiratory and immune function as well as providing cardiovascular and anti-oxidant benefits. The active ingredient is the pungent smelling, organo sulfide compound “Allicin”. When garlic is crushed, Allicin is activated which is the tear-causing, “sulfur” smell we experience and so do insects. Grape Seed Meal is also a powerful antioxidant comprised of Vitamin E, flavonoids, and the polyphenols, oligomeric proanthocyanidin (OPCs) making grape seed extract an excellent cellular defense source, working synergistically with garlic to support immune function, cardiovascular and blood vessel health. Diatomaceous Earth is deadly to an insect, but completely harmless to animals. Diatomaceous Earth is a non-toxic, white talc like powder and has been known to improve digestive health along with antimicrobial and anti-parasitic benefits Distillers Grain is an important ingredient. As a carrier for the other ingredients in Barrier, it contains protein, fat, minerals and vitamins. Distillers Grain is a by-product of dry mill ethanol production. ACTIVE INGREDIENTS: Garlic 3600mg, Grape seed 600mg, Diatomaceous earth 600mg, Thiamine HCL 300mg, Calcium Carbonate 4500mg