Treblab XR500 Wireless Bluetooth In-Ear Headphones w/ Mic $22 at Amazon
Amazon with Productech has the Treblab XR500 Wireless Bluetooth 4.1 In-Ear Headphones with Mic (Black) for $30 - $8 off coupon (clip green coupon) =
$22 with free shipping on $25+ or with Prime.
Works up to 9 hours on a single charge, and has a 20Hz-20kHz frequency response range.
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