4mm ultra-thin size makes it can be easily and conveniently put it in your wallet, pocket to record important voices in life. With large memory and battery capacity, it has a large storage for recording and can work for a long time. Made of zinc alloy material, the recorder is durable and reliable to use. It is built-in 750mAh high-capacity battery and can record continuously for about 150 hours. It is equipped with 3.5mm wired earphone, supports MP3, recording playback, volume adjustment and track switching. The length of the product is 8.6cm, the width is 5.4cm, the height is 0.4cm. It has a wide applicability and can be used for business, conference, interview, etc. Memory and power can be saved since that it will record automatically when there is sound and stop automatically for no sound.   Parament: Item Name: Voice Recorder Material: Zinc Alloy Memory: 32GB/8GB/16GB Optional Battery: Built-in 750mAh Rechargeable Battery(Included) Recording Method: Power-on for Recording, Power-off for Storage Charging Time: about 3 Hours Recording Time: about 150Hours Sampling Rate: 48KHz Recording Bit Rate: 192Kbps Recording Format: WAV Playing Format: MP3, WMA, WAV Thickness: 4mm Earphone Interface: 3.5mm Features: Large Storage, Stable Performance, Portable Size Details: 8.5cm x 5.3cm x 0.4cm/3.35" x 2.09" x 0.12" (Approx.) 8GB Recording 90hours,16GB Record 170-180hours, 32gb record 350-360hours   Notes: Due to the light and the screen setting difference, the item's color may slightly differ from the pictures. Please allow slight dimension difference due to the manual measurement. Package Includes: 1 x Recorder 1 x Charging Cable 1 x Charging Cable 1 x Recorder