The WT-USB adapter is a CD changer emulator for factory Mazda car stereos. It allows adding modern traditional connectors for mobile devices and portable electronics – AUX and USB – to the car's audio system.

Connector: 8+8-pin
Does not distort or degrade sound quality
Controllable via buttons on the stereo or steering wheel
Audio format support: MP3 and WMA
Signal-to-noise ratio: 90 dB
Frequency range: 20-20000 Hz
Power supply voltage: 12 V
Includes a USB card reader with slots for SD, SDHC, and MMC memory cards, as well as an English instruction manual

The device is not compatible with "Multi Function Audio System" stereos, new cars with CAN bus, or satellite and navigation systems. For Mazda RX-8 models, the radio's software must be version 9.55 or higher.
Compatible car models:

Mazda 2 (2003-2008)
Mazda 3 (2004-2008)
Mazda 5 (2005-2009)
Mazda 6 (2002-2009, audio systems in 2003-2005 models must have a soldered jumper on the L716 chip)
Mazda CX-7 (2007-2008)
Mazda Miata / MX-5 (2003-2008)
Mazda MPV (2002-2011)
Mazda Protege (2002-2008)
Mazda RX-8 (2004-2008)
Mazda 323 / Familia (1999-2003)
Mazda Premacy (2002-2008)
Mazda Tribute (2003-2006)