Electric Diffusers
Lamp Ring Diffusers

Passive terracotta/clay diffusers are simple to use and very affordable. They are typically made of a porous material and can be placed in small areas like cars, offices or bathrooms. They require no electricity or clean up. Just put your favorite oil scent directly onto the disk or into the vessel. Perfect for places where you are want subtle aromatherapy. Since they use natural evaporation rather than a heat source they are safe to use unattended.