Each unit has a fan inside to force the aroma throughout your space. Weather you share a bathroom at the office or sit next to someone that just doesn't believe in showering everyday. Everyone would rather smell citrus, woodlands, mulberry... any other smell! It is known that a good smell triggers your senses to calm and sooth or give you energy. We maintain each unit each month! We check the fan, change the battery if needed.. and refill your fragrance. For as low as $10.00 a month! Discounts available for multi-unit, pre-pay for the year as well as refer a friend!