Tenergy via Amazon offers the Tenergy T20 Bluetooth Headphones w/ Armband for $24.99. Coupon code "AIC9H9VM" cuts them to $17.49. With free shipping for Prime members, that's tied with last month's mention as the lowest price we've seen. (It's the best today by $12.) Features include Bluetooth 4.1, CVC 6.0 noise isolation, IPX7 water resistance, and a 30-foot range. Deal ends January 13.