The CDJ-850 builds on the DNA of its predecessor, the CDJ-800MK2 and adds some serious enhancements. With its full-sized jog wheels, large screen and pro-DJ features, it feels and functions like a CDJ-900NXS or CDJ-2000NXS – without the top-flight price tag. The CDJ-850 is rekordbox-ready or you can use the USB-HID interface to control the DJ software of your choice.It still plays your MP3, AAC, WAV and AIFF files stored on USB devices.You can use this product to control rekordbox dj software. rekordbox dj is a rekordbox Plus Pack that unleashes performance features including Hot Cues, Sampler, Slicer, Sound Colour FX, Beat FX, Beat Jump and Pad FX. Simply buy rekordbox dj, activate your licence key, and start DJing.The large screen displays track information including title, artist and BPM and waveforms, while the rotary knob makes browsing and selecting tracks a breeze.