I bought these to fill for homemade gifts, car air fresheners. I got the idea because I was given a similar product and I have enjoyed using in my car. It diffuses slowly and once the original scent was used up I refilled with essential oils. To use, you partially loosen the wooden cap and turn the bottle upside for a few seconds. Then tighten the car and right the bottle. The scent diffuses off the wood cap.
I haven't used these yet, but filled one and it seems that it will work nicely. It comes with a plastic stopper that can be used to secure the bottle for gifting but would be removed to use as a car air freshener.
The listing suggests the product could also be used as a necklace so I feel compelled to mention the cord would not be long enough for that. It also suggests one might want to use this as a travel bottle but I think that is unlikely as it is very small. I felt they were a bit expensive for what they are but appreciate being able to purchase unusual items like this on Amazon and have them delivered to my house.