CD/MD cassette adapter play any portable CD player and Mini Disc player through any audio cassette player. This product enables any portable CD or MD players with a built-in headphone jack, to be heard through the speakers of any cassette playback system. This includes automobile and all portable cassette players. DC Adapter with 800mA output powers portable CD players & Mini Disc players through your car's cigarette lighter. The product is a high quality 800mA regulated DC adapter with the ability to convert the power from your car cigarette lighter. The following power Output selections are available 1.5,3,4.5,6,7.5,9 or 12Volts, you may use this product with most portable cassette players, radios, CD players, Hand held Games, Keyboards, Calculators,& many other battery operated appliances. This unit also has reversible polarity to allow you to use it with products that have either Positive Or negative center pin.