TomTop offers the Docooler R39 4K 3D Smart Android TV Box for $15.99 plus $5.15 for shipping. That's a buck below our mention from a month ago and the lowest price we've seen. (It's the best deal now by $4.) It features a Rockchip RK3229 1.5GHz quad-core processor, 1GB RAM, 8GB flash storage, support for resolutions up to 4096x2160 (4K), 3D support, 802.11n wireless, Ethernet, HDMI, four USB ports, SD card slot, Android 6.0 OS (Marshmallow), and remote control.

Note: The countdown timer on the product page does not reflect an actual expiration time and resets daily.