The collars, which contain the chemical tetrachlorvinphos, make up more than half of flea and tick collars sold in the U.S., according to the EPA. They are much cheaper than many name brand collars and are largely aimed at low-income pet owners.
The collars, which contain the chemical tetrachlorvinphos, make up more than half of flea and tick collars sold in the U.S., according to the EPA. They are much cheaper than many name brand collars and are largely aimed at low-income pet owners.