4GB Internal Storage with Expandable microSD Slot Direct USB (Slide， Store) Digital Pitch Control Voice Operated Recording Intelligent Noise Cut Built-In memory 4GB PC Connectivity Yes Channel Stereo Recording Format MP3 Playback Format MP3 Messages/Folders 4074/20 (199 messages in 1 folder) Earphone Jack Yes Battery type Dry Battery ( Alkaline， Size AAA ) x 2 Dimension (W x H x D) Approx. 37 .2 x 113.2x 19.3 mm Weight (including batteries) Approx. 75g Mic-In Jack Yes MP3 (44.1kHz， 128kbps) Approx. 57 Hrs Max. Recording Time 128kbps Recording Time 67 Hrs 05 Min Number of MP3 Songs (128kbps， 1 song = 4 min) Approx. 1006 songs MP3 music playback Yes