Product Details： Mini Bluetooth 5.1 Audio Adapter - With Upgraded Version Of Bluetooth 5.1 Technology, Enjoy Non-inductive Delay To Improve Call Sensitivity And Connection Stability. You Just Need To Connect It With Non-bluetooth Devices, Then They Can Be Upgraded To Bluetooth Devices, And The In-ear Earphones Can Effectively Isolate Noise And Enjoy Music Easily. Wide Compatibility - Audio Receiver For Headphones, Home/car Stereo. Works With Most Devices Like Phone, Tablet, Laptop, Most Speakers, Etc. The Standard 3.5mm Audio Adapter Is Suitable For Any Powered Pc Speakers, Car/home Stereo Sound System And Wired Headphones. Safe Hands-free Calling - Provides You With The Safety And Convenience Of Hands-free Calling While Driving. The Adapter Equipped With Noise Cancellation Technology, Suppress Environmental Noise, Pick Up Human Voices More Accurately, And Easily Listen To The Sound Quality Of Cd Records. New Upgrade Two Modes - Freely Switch Between Bluetooth/tf Card Modes, Support Wav/flac/ape Lossless Format Playback.