The active ingredient found in Optigard cockroach Gel Bait, Emamectin Benzoate, is a synthetic derivative of Abamectin, which can be found in Avert DF.
There is not an exact number when it comes to coverage since it depends how much and how often you use Optigard Cockroach Gel Bait.
Please read the instructions bellow to help you get an idea of how much is needed:
Each bait spot should equal approximately 0.25 to 0.50 grams of product (a spot approximately 3 mm or 1/8 inch in diameter equals 0.25 grams of product, while a spot approximately 6 mm or 1/4 inch in diameter equals 0.50 grams of product).