Quality 316L Stainless Steel. Just slides on to the air vents in your car.
Price includes 3 foam pads - please add colours to checkout (can be same or mixed). If no pads added, random colours will be sent. 
Add 2-3 drops of essential oil on to foam pad and enjoy the aromatherapy benefits. Once aroma fades just add another drop or 2 of oil depending on your preference.