Hercules DJ 4 Set Built-In Audio - 4-channel Output: Stereo Line Output for the Mix, Stereo Headphone Output for Previewing Tracks; Microphone Input with Talk-Over Function Large DJ Controller for Mixing, Compact Enough for Mobile Use Jog wheels - Touch detection activated by weight of user's hand; Large: 12cm (4.7") diameter/1.5cm (0.6") height Built-In Audio - 4-channel Output: Stereo Line Output for the Mix, Stereo Headphone Output for Previewing Tracks Microphone Input with Talk-Over Function Built-In Audio - 4-channel Output: Stereo Line Output for the Mix, Stereo Headphone Output for Previewing Tracks; Large DJ Controller for Mixing, Compact Enough for Mobile Use Jog wheels - Touch detection activated by weight of user's hand; Large: 12cm (4.7") diameter/1.5cm (0.6") height Microphone Input with Talk-Over Function