.....The LaCie Rugged RAID ships with the 4TB hard drive itself, which includes a protective orange rubber cover, a spare port cover, a quick start guide, a USB cable, and a power adapter for use when the hard drive is plugged in via USB 3.0. There are also several plug adapters to accommodate travelers.
Article Link: LaCie Review: Hands-On With the 4TB Rugged RAID Thunderbolt Hard Drive
The LaCie website itself mentions two HDDs. They don't however mention whether those drives are of the 7200 or 5400 RPM variety. At the quoted transfer rates for striping, most likely 5400 or perhaps even 4500.
It's nice that the drive comes with the integrated TB cable, but hopefully that cable is of better quality than the included TB cable they shipped with previous TB drives. If you're out in the field, with no place to plug in the power adapter, that USB3 port is of little use if the TB cable fails.