Bio Spot Flea And Tick Dip For Cats And Dogs Gives A Quick Knock Down. Pyrethrin dip kills fleas, ticks, lice, knats, flys and mosquitoes on contact and repels them. Eight ounce bottle of concentrate. May be used every seven days. Do not use this product if you are using a spot on treatment. If you have fleas be sure to treat your home and lawn.