with just one key, easy to operate. 4 TF cards with different storage for optional - 4GB (72hrs Storage Time), 8GB (144hrs Storage Time), 16GB (288hrs Storage Time) and 32GB (576hrs Storage Time). Voice Control/Line-in Function - Comes with voice control function, Turn it on and will auto recording when there have sound. Support line with other equipment such as telephone to recording. Adjust the volume, fast-forward and fast rewind, and A-B repeat operation functions you can operate. Powerful Battery Strong Compatibility - The voice recorder with built-in 400mAh rechargeable battery can record continuously for 13hours. Compatible with Win7/8/10 etc. Easy to Operate - One button for one steps, 1.2inch screen with backlight, convenient to recording and reading the font at night. You can delete the files on the recorder, and connect with the computer via USB cable to download and upload. Available in a Variety of Scenarios - Ideal for your business meetings, negotiations, interviews, presentations, conferences, semester classes, presentations, group discussions, etc., accurately record all the details. Specification: Color: Black Product Size: 10 x 3.5 x 1.2cm/4 x 1.4 x 0.5in Product Weight: 40g/1.6oz Storage Capacity: 4GB: 72hrsStorage Time 8GB: 144hrsStorage Time 16GB: 288hrsStorage Time 32GB: 576hrsStorage Time Music Play Format: MP3, WAV Recording Format: Standard(SP) MP3 Recording Sampling Bit Rate: 192kbps Frequency Response: 20HZ-20khz SNR: 70 db Support system: Win7/8/10 etc. Battery: 3.7V 400MAH Lithium Battery Recording Time: 13hrs Support System: Win7/8/10 Package Size: 15.5 x 8 x 4cm/6.1 x 3.1 x 1.6in Package Weight: 112g/3.9oz Packing List: 1 x Voice Recorder 1 x Earphone 1 x USB Cable 1 x User Manual