Termior is a brand name under which BASF sells Fipronil. Termidor is used as a conventional barrier treatment for termites. The product is used to apply a barrier to prevent termites from attacking structural wood. Termidor differs from older barrier treatments in that it does not repel termites. Instead, termites enter the treated area and receive a lethal dose of the insecticide. Termidor has another unique attribute in that contaminated termites can transfer the insecticide to other termites. Thus termites who never came in contact with the treated surface can still die.