To use the car diffuser: 1- Unscrew the cap 2- Remove the plastic at the opening 3- Screw back on 4- Place in your car Please ensure that the scent does not escape from the diffuser to avoid damaging your vehicle's plastic. You can find the car diffuser on our website, ideal for scenting the interior of your home using ventilation. The preservation of your car diffuser will depend on your driving habits, meaning the more you open the windows, the more the diffuser will be used, and the more you use the ventilation, the more it will also be used.