Boss Micro BR Digital Multitrack Recorder Ultra portable, only slightly larger than an iPod. 4-track playback, 32 V-Tracks. Loads and plays MP3 files. Multi-effects onboard; dedicated guitar input. Time-Stretch and Center Cancel features (including MP3 files). Drum machine with 293 rhythm patterns. Built-in tuner and microphone. USB port for data transfer. SD Card slot for recording media, 128MB card included.