Hit Cockroach Chalk is most potent and kills the cockroaches and ants which should never come into your home.It's as simple as a line across the floor. Keep your home free of ants, cockroaches and other crawling insects with HIT Chalk. Draw a line across the floor or any other surfaces where these pests frequently crawl. These will be killed the moment they cross this line. So you can be sure they wouldn't dare cross the HIT Chalk line.