Check the listing for details. 4PCS Rectangular Sign Holders with Cross-shaped Sockets for Posters + Images NEW. Color: Black, Condition: New. Listed at 35.98 USD. Feature： NO WATER NEEDED - unique system making this machine water free allowing better scenting coverage. POWERFUL LONG-LASTING DIFFUSER: This essential oil diffuser is powerful easily filling a space with fragrance. QUIET: The noise from our diffuser is under 42dB so will effectively blend with the ambient noises in your surroundings, creating a unique and inviting ambiance in your home. WALL MOUNTED:Stylish design will blend perfectly with your décor and creates an aromatic paradise at home, the office, spa, massage or physical therapy studio. This diffuser can be wall-mounted, or sit on a flat surface like a bookshelf or top of your refrigerator, plugged in a regular outlet. DO NOT LAY FLAT!.