A 100ml bottle of your chosen oil to refill your existing reed diffuser. If you are wanting to continue with the same fragrance, these are ideal to save you the cost of replacing the diffuser when there may be no need. 
 
We would recommend you order a new diffuser if you are going to be changing scent.
 
When ordering a refill you may also want to renew your reeds, which can also be purchased seperately.