Power supply adapter. Features: Formerly known as MX-Charge, the MX-PSU accessory is an optional AC wall adapter power supply with USB-C connector for some of the Sound Devices MixPre Series of audio recorders. It is included with the MixPre-3M and MixPre-6M, and is an optional accessory for the MixPre-3 and MixPre-6. Includes adapter plugs for US, UK, Australia & Europe.