The Adaptil Dog Calm Home Diffuser and Refill is a dog appeasing pheromone emitting diffuser recommended for dogs and puppies with fear and/or stress related behavioural issues. TheAdaptil Dog Calm Home Diffuser and Refill naturally calms and reassures puppies and dogs in times of stress. The Adaptil Dog Calm Home Diffuser and Refill lasts for up to 4 weeks when plugged in to power point and used continuously. The Adaptil Dog Calm Home Diffuser and Refill should remain in close proximity to the dog for effectiveness. The Adaptil Diffuser and Refill comes with a 48ml vial so you can use the product straight away. Refill vials are available for individual purchase when they run out.