The Cigar Oasis Ultra 4.0 Electronic Humidifier offers a reliable and worry-free solution to keeping your premium cigars properly humidified. Its reliable built-in fan ensures consistent humidity distribution. The large on-screen display shows the humidor’s current relative-humidity and temperature. Easily mounts to the humidor’s lid. Its slim design uses minimal space. Adjust the humidity setpoints with the touch sensitive buttons. Remotely monitor your humidor’s internal relative-humidity and temperature with the optional Wi-Fi compatible Cigar Oasis SmartHumidor app (available for Apple and Android devices. Subscription required.) The Ultra 4.0’s pre-treated water cartridge requires distilled water only, and it requires refilling every 2 to 6 weeks. Perfect for 50 to 100 cigar capacity humidors (up to 2.0 cubic feet). Comes equipped with a Control Top, Water Cartridge, Magnetic Mount, Ribbon Cable, and USB/Power Adapter. Dimensions: 7"L x 2.5"W x 1"H.