These are hanging glass car diffusers. You can use them in a car, locker, or any small space. They will last up to 45 days depending on how often you refresh the scent. Instructions: unscrew wooden top, take plastic cap off, screw wood top back, turn it upside down until top is damp, and hang up. If product leaks, clean up right away. Various Shapes will be sent (smooth or jeweled glass)