Zotac is pretty much the inventor of mini PCs as we know them and the ZBOX style is probably their most known series. The newest member of the ZBOX family is Skylake based and called the ZBOX MI551.
The MI551 is equipped with an Intel Core i5-6400T quad-core processor that runs at a core speed of 2.2GHz and has a boost speed of up to 2.8GHz. The system allows for up to 16GB RAM to be installed in the two DDR3L-1600 SODIMM slots, so no DDR4 in this system.
The ZOTAC ZBOX MI551 uses the CPU built-in GPU in the form of an Intel HD Graphics 530 that supports the two DisplayPort connections for up to 4K UHD at 60Hz and the HDMI port with UHD resolutions at up to 24Hz in multi-screen mode and 60Hz with just one panel. So this tiny system is fully 4K ready.
Internally it has room for one 2.5-inch SATA SSD or HDD as well as one M.2 SATA SSD (42, 60, or 80mm length) and externally it features a combined card reader and USB 3.1 combo port for easy readout of memory cards.
Other than the previously mentioned connections you get stereo jacks for microphone and headphones, one USB 3.1 Type-C, two USB 3.0, one USB B2.0 and two Gigabit Ethernet connections. The MI551 also features a built-in 802.11ac and Bluetooth 4.0 wireless card with external antenna.
There is an optional Plus model available as there usually is with the ZBOX systems where you, in this case, get 4GB memory and a 120GB M.2 SATA SSD pre-installed for out-of-the-box usage.