4lb Plain Salt Brick – For free-choice livestock feeding in feedlots, and on pastures and ranges where grain, forage and water is often deficient in sodium chloride and iodine. Lactating animals require further supplements due to excretion in milk. Salt deficiency reduces growth, weight gain and milk production. Bricks are for feeding in stalls, stanchions or on pasture posts. For all classes of cattle, sheep, and horses.