The Vintage MFG-557 Deluxe Morse Code Practice Oscillator Straight Key by MFJ is a reliable and well-crafted device made in Taiwan. This oscillator key features volume controls, making it an ideal tool for practicing Morse code. With its sturdy construction and attention to detail, this working vintage piece is a must-have for any radio communication enthusiast looking to improve their skills in Morse code transmission. Includes 12 Volt Power supply. Very good used condition.