(Merck) Fenbendazole controls over 99% of all the major worms in cattle, including lungworms and intestinal and stomach worms. No known side effects, even for stressed cattle. Each 92 gram tube treats 8-500 lb. calves. Each 290 gram tube treats 25-500 lb. calves. 290 gram tube requires 4-tab dispensing gun. Safe for dairy cattle, no milk withdrawal.