This cat calming pheromone set includes 2 diffusers and two (2) 48ml refills, providing a total of 96ml of soothing scent for cats of all life stages. The color of the diffuser is purple and it is manufactured by TopSum, a trusted brand in pet supplies. The diffuser is designed to help your house-cats feel more relaxed and comfortable. Reduce stress related to feline scratching, urine marking, multi-cat contact, loud noises, alone at home, new environments, or vet visits. Easy to use: plug into an outlet nearest where your cat spends the most time. For more details about how to use this product, please read the instruction manual included in the package. The set is guaranteed to be odor-free making it a great solution for behavior training and creating a calm environment for your furry friends. SHIPPING IS FREE via USPS, and I ship within 24 hours of payment. Thanks for looking!