Freshen up your shelves with the Scented Candle Diffuser! This diffuser has a round candle viewing window in front and a square opening in the back for easily changing the candle. We recommend a 2" tall candle for use in the Scented Candle Diffuser. The inside area where the candle sits is 3-1/2" tall. There is an indented area on top for adding potpourri, oil, or scented wax. Caution: Do not leave open flames unattended. The diffuser may get hot while the candle is burning. Candles not included.