This is a cattle wormer. The drawback to this is that it should not be used on birds kept for meat or eggs, thus it is used mostly in show birds. Diesel fuel has also been used by some people. Dip their legs in once a week for two weeks. Dip legs in or use a brush to apply.
Some people say once a week for a few weeks, some say once a day for a week.
Mites are very difficult to see - they are gray until they suck your chicken's blood and turn red. Mites can be so numerous that they will cause anemia and death of a chicken. They will cause what appears to be sores on the chicken, particularly around the vent and comb. It is important to allow the birds to use dust baths - this is a natural way for them to rid themselves of mites. Dust baths are just sections of soft earth that the chickens can scratch and throw the dirt amongst their feathers.