O Oasis, 4-String Ukulele, Original Version (OH-18) Description Oasis Ukulele Humidifier. With two unique features, the mounting system allows the humidifier to hang horizontally inside the ukulele rather than vertical (like the guitar humidifier). Secondly, the humidity output is about 50-Percent of the Royal Blue Oasis guitar humidifier, to accommodate the smaller instrument size. This also allows the humidifier to last twice as long between refills. Features: You can see when Oasis is ready for refill Long lasting humidification Won't leak due to overfilling Two levels of leak protection Stabilized to never touch the body of your instrument Product Details: Brand: O Oasis Color: Original Version Item Dimensions LxWxH: 1.25 x 1.25 x 4.5 inches String Material Type: Nylon Instrument: Guitar, Ukulele Operation Mode: Evaporative Number of Strings: 4 Item Weight: 1.13 ounces Product Dimensions: 1.25 x 1.25 x 4.5 inches Item model number: OH-18 Is Discontinued By Manufacturer: No Date First Available: January 29, 2010 Color Name: Original Version String Material: Nylon Number of Strings: 4 Power Source: Corded Electric