1 Voice quality equalizing. 2: Flexible USB plug 3: Build-in high fidelity speaker 4: 5 play mode,6 EQ mode 5: Dot matrix LCD display 6: Battery power indication, auto-protect function. 7: MP3 format recording, MP3 music player. 8: Multi-audio source recording. 9: FM function 10: Memory/Record Time (Hour):128MB/35H 256MB/70H 512MB/140H IGB/280H 11: A , B , C ,D 4 folder max storage capacity up to 4*99 files 12: Display residual memory space 13: MIC (recording) sensitivity adjustment 14: Synch recording , subsection recording automatically depend on the signal 15: Auto-power off: power off automatically when no operation continuance 30secs. 16: Alarm when the storage space less than 1 min. 17: low voltage alarm: the battery power showing by 3bar , the unit can not be operated when the battery voltage less than 2.0v. 18: USB1.1 communication jack , enable recording date up/down loading between PC & recorder 19: Memory/Record Time (Hour):128MB/35H 256MB/70H 512MB/140H 1GB/280H