?12 Months Warranty? 12 months money back guarantee, 100% satisfied customer service. Please contact if you have any questions in use!. ?Music format support? Full format lossless mp3 player, WMA, OGG, APE, FLAC, WAV, AAC-LC, ACELP format playback; Video format support:720P/1080P full format HD video playback, such as RM, RMVB, AVI, MKV, WMV, VOB, MOV, FLV, ASF, DAT, MP4, 3GP, MPG, MPEG, etc., directly play without conversion. ?2000mAh Long Battery Life?M501 built-in 2000mAh battery provides a longer playback time, approx 19H of music with the wired headphones; Bluetooth approx 6H, (Note: The playing time depends on the volume, speaker, Bluetooth, and other factors. The above time is for reference only and the testing standard is maximum screen brightness, the screen is always bright, and the volume is 100% loud.). ?Wireless Bluetooth?M501 mp3 player uses bi-directional connection technology for faster and more stable connection, and supports compatibility with more types of Bluetooth headphones, Bluetooth speakers, car speakers and cell phones. Also, the mp3 player has an auto-connect function, which can automatically match your Bluetooth device after startup, it reduces the complex file transfer of traditional mp3 players It can well transfer files from your phone to the player via Bluetooth function. ?Smart WIFI wireless connection?MP3&MP4 player with 4.7 inch high resolution (1280*720) full touch screen,M501 MP3 player supports downloading/uploading/listening music or watching videos online after you connect to WiFi. This MP3 player covers various mainstream media app such as: Music, Apple Music, Spotify, Facebook, Audible, Deezer, Kindle, Pandora, Twitter, TIDAL, FM Radio, Voice Recorder, Video, etc. ?Smooth Android OS? The MP3 player with Bluetooth and WiFi is powered by Android 8.1 OS, 8-core 1.92GHz processor, 3GB RAM and 16GB ROM with 64GB SD card, which makes it run faster and smoother, it not only ensures stable operation performance but also supports your expansion needs.