Bluetooth Adapter And Wireless Audio Receiver With Microphone And 2.5Mm Jack For Product Features Custom Made for Sennheiser HD Series Wired Headphones. This wireless music adapter works as a wireless audio streaming converter for the Momentum series headphones, Sennheiser HD598 / HD598Cs / HD598SE / HD595 / HD599 / HD559 / HD569 / HD579 / HD518 / HD558 Headphone replacement cable cord connector and converter. Excellent Sound Quality. This Bluetooth audio receiver has a dedicated Texas Instrument headphone amplifier chipset built-in which makes it more dynamic and rich in details. The output is much more powerful, it can drive the over ear headphones with larger impedance, so this is a wireless receiver plus a headphone amplifier and it is perfect match for Sennheiser HD series headphones. Optional Bass Boost Feature. Airfrex Bluetooth receiver has preset EQ function which allows users to turn on or turn off the bass enhancement feature if needed, this feature can compensate the bass performance for their headphones or speakers, users just need a simple double click to switch this function. Latest CSR Bluetooth 4.1 Chipset. This wireless stereo adapter applies the most advanced CSR Bluetooth chip which ensures this is lossless in audio transmission which is a huge difference from those low quality Bluetooth adapters. You need a high quality headphone adapter for a good Sennheiser headphone. Built-in Microphone for Phone Call. Our music adapter also has built-in Microphone which allow the users to pick up or end a phone call by a simple press on the button, so they won?t miss any phone call even during music listening. Shipping: Shipping is complimentary within the lower 48 US States. We Do Not Ship to PO/APO Boxes, HI or Alaska We Do Not Ship Outside of the Continental US All items ship within 24-72 hours of Payment For large items that require Freight shipping a valid phone number is required to call and schedule your delivery Terms of Sale and Feedback: Feedback is extremely important to us and If you are satisfied with our transaction, please take a moment to leave Positive Feedback. YOUR Satisfaction is our #1 Priority! If there are any issues, PLEASE contact us BEFORE leaving a neutral or negative rating so that we may resolve any concerns. We PROMISE we can make you happy if you give us a fair chance. Returns / Concerns: All items qualify for returns within 14 - 30 days of receipt. Buyer is responsible for return shipping on any item that is not damaged Please be sure this is an item you want before making your purchase. Customer Satisfaction is our TOP priority! All items are IN STOCK at time of listing. Inventory changes constantly and it is impossible to maintain a perfectly accurate count of all items. Please do not penalize us if we have to issue you a refund! Thank You For Your Business!