What are the key system specifications of this Buffalo TeraStation desktop NAS?

This desktop NAS uses an Intel Atom C3338 1.5 GHz dual-core processor, has 8 GB of installed memory, and is configured with 4 TB x4 included HDDs for 16 TB total storage.

What hardware comes included with this TeraStation WS5420DN16W5 NAS?

It includes 4 x 4TB HDDs for a total of 16TB of included storage, along with an AC cable, a 6a Ethernet cable, a front panel key, a warranty statement, a quick setup guide, and setup media (SD card).