The Otamatone Sweets Mint Green is a battery-powered musical instrument with 49 keyboard keys made of plastic. It is a Japan import and comes in a new, unopened box. The product dimensions are 5 x 14 x 3 inches and it weighs 2.08 ounces. The Otamatone is a unique instrument that produces sound by squeezing its flexible "mouth" and sliding your fingers along the neck.