Patuoxun via Amazon offers Prime members the Mpow Bluetooth 4.0 Audio Adapter for $30.99. Coupon code "MPOWAPTX" cuts it to $22.99. Prime members bag free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, it adds $5.14.) That's a buck under last month's mention and the lowest total price we could find by $11. This adapter can be paired with a Bluetooth device and provides audio data to a receiver via 3.5mm jack.