Proker via Amazon offers its Proker Wireless Bluetooth Headphones for $39.80. Coupon code "YUW7J6R5" drops it to $27.86. With free shipping, that's tied with our mention from a week ago, $12 off, and the lowest price we could find. They feature Bluetooth 4.2, up to 2.5 hours of playback, and compatibility with iOS or Android devices. Deal ends December 28.