40 POUND Removes ammonia from the air by absorption. The ammonia in urine is trapped within the molecules of sweet pdz for freshair. Unscented so it does not mask odors. Dries as it deodorizes. Moisture is absorbed by sweet pdz and remains effective even when capacity is reached. Sweet pdz can be recycled after use by applying the bedding that contains the pdz to gardens, pastures and compost. Serves as a slow release nitrogen/potassium fertilizer.