• MICRO CASSETTE SYSTEM uses ultra-compact easy to obtain
• micro cassettes for recording and playback convenience
• SLIDE SWITCH OPERATION slides into position with one finger and
  changes the operating mode from Dictate to Stop to Listen to Backspace
• METAL CASE is designed to withstand rugged use while dictating in or
  out of office, in the car, or elsewhere
• VOICE OPERATED RECORDING (VOR) activates the recorder only
  when audible sound is present, conserving tape and eliminating
  soundless pauses
• LOCK SWITCH locks controls to prevent accidental activation of
  any function
• DICTATE/CONFERENCE SWITCH enables the unit to record in different
  situations such as for individual recording or in meetings
• FAST PLAYBACK FUNCTION reduces the time needed to review
  recordings
• FAST FORWARD/CUE allows listening to the tape at high speed to locate
  specific passages for editing
• LED RECORD/BATTERY INDICATOR verifies when unit is in Record mode
  and confirms battery strength
• 3-DIGIT TAPE COUNTER gives you a visible measure of tape elapsed for
  rapid access when editing and listening
• 2 RECORD/PLAYBACK SPEEDS gives you the option of using a standard
  micro cassette for an extended recording or dictation session as long as
  2 hours
• AUDIBLE END OF TAPE ALARM sounds an audible alert when the end of
  tape is reached
• MICROPHONE JACK lets you connect an external microphone if desired
• EARPHONE JACK for private listening with optional earphone
  specifications
• TAPE SYSTEM: 4 track, 1 channel monaural micro cassette
• FREQUENCY RESPONSE: 300 - 4000Hz at 2.4cm/sec 300 - 3000Hz at 1.2cm/sec
• MICROPHONE: Built-in electret condenser
• INPUTS: DC In, 3V; External Microphone
• OUTPUTS: Earphone mini jack
• SPEAKER: Mono: 1” (28mm) dia. x 1
• POWER OUTPUT: 250mW (at 10% THD)
• POWER REQUIREMENTS: DC 3V with “AAA” x 2 Batteries
• AC 120V 60Hz with optional AC Adaptor
• BATTERY LIFE: Approx 7 hrs with Sony alkaline batteries (not incl.)
• DIMENSIONS (WHD): 2 5/32" x 4 3/4" x 29/32" (54.5 x 120 x 22.4mm)
• WEIGHT: 5.9 oz (165g) with batteries

Specifications

• Tape System 4 Track, 1 Channel Monaural Cassette
• Frequency Response 300-4000Hz at 2.4cm/sec
  300-3000Hz at 1.2cm/sec
• Microphone Built-In Electret Condenser
• Inputs DC In, 3V; External Microphone
• Outputs Earphone Minijack
• Speaker Mono: 1" (28mm) dia. x 1
• Power Output 250 mW (at 10% THD)
• Power Requirements DC 3V with "AAA" x 2 Batteries
  AC 120V 60Hz with optional AC Adaptor
• Battery Life Approx 7 hrs with Sony alkaline batteries (not incl.)

When you order this item you will get a Sony BM575 or a Sony BM577 depending on Availability. They are the Same Machine with a few extras on the Sony BM577 a like battery meter and a "Cue button".