Ultra-Slim Design Ultra-slim audio jack adapter extends the reach of any 3.5mm (1/8”) cable/plug through thick mobile device cases. Connect your iPhone, iPod, MP3 player, CD player, smartphone, tablet or any audio device with a 3.5mm (1/8”) headphone jack to your headset with microphone, credit card readers, car, office or home audio system. 4-Conductor Tip-Ring-Ring-Sleeve (TRRS) Connectors FosPower 4-conductor TRRS AUX stereo audio adapter has an additional conductor that allows you connect your 3.5mm (1/8") headset that supports microphone and volume control/play/pause/call/hangup features. It is also compatible with credit card readers such as Square Reader, Amazon Register Card Reader, and PayPal Here Card Reader. Also works with voice commands such as "Siri" and "Ok Google". Beveled Plugs Beveled step down design plugs ensure FosPower premium stereo audio adapter to be fully seated into audio port and compatible with most cases in the market. 24k Gold Plated Connectors FosPower premium stereo audio adapters are 24k gold plated and resist oxidation and tarnish. Limited Lifetime Warranty This product comes with a limited lifetime warranty. Please refer to FosPower's website for more information. Connectors: 1 TRRS mini-stereo (3.5mm) male to TRRS mini-stereo (3.5mm) female Works with any device with a 3.5mm headphone jack including headset with microphone, credit card reader readers such as Square Readers, PayPal, car, office or home audio system. Also compatible with voice commands such as "Siri" and "Ok Google". 24k gold plated connectors resist corrosion and reduce tarnish