The general layout of the Define R3 is fairly standard. The drives go in the front of the case and the motherboard and power supply in the back. While the case is made of steel, there are no sharp edges to be found, as the steel edges are either rolled or covered with a rubber lining. Various shaped/sized silicone grommets are located along the edge of the motherboard tray to allow for the tidying up of cables and wires. Other than the screws to hold down the fans and motherboard, everything else uses tool-less thumbscrews. There is an additional 120mm fan bracket at the bottom of the case. This fan slot has a dust filter.
The slot covers are ventilated and held down by thumbscrews. They're black and look great in the white case. In the power supply bay, there is a foam liner along the edge of the opening and rubber nubs at the bottom of the case for the power supply to rest on. These added touches aid in Fractal Design's mission to make the Define R3 quiet, by reducing vibrations which cause noise. For power supplies designed with a cooling fan on the bottom, there is a filter covered vent which supplies cool air to the power supply.
The front of the Define R3 has two (2) 5.25" and eight (8) 2.5"/3.5" drive spaces. The 5.25" drive bays come with thumbscrews to hold installed drives in place, and one 5.25" to 3.5" adapter rack is included. The 3.5" drive spaces have racks to install the drives on, and the rack easily slides into place. The racks are locked into place with clips on either side of the drive, and can also be screwed to the case itself for extra security.
The racks are plainted black steel There are mounting holes for both 2.5" and 3.5" drives. The mounting holes for 3.5" drives include silicone grommets to reduce vibrations caused from mechanical hard drives. The 2.5" mounting holes do not have silicone grommets, as the drives installed using these holes will typically be SSDs (solid state drives) in a modern computer system, and SSDs do not have moving parts (and thus don't create vibrations).
The back of the motherboard tray is where cables are usually routed for users who want a clean look for the inside of the computer system. The inclusion of passthrough silicone grommets and slots to pass ties through help facilitate this. A large hole is included behind the top of the motherboard tray to allow for the changing and installation of CPU coolers without having to remove an already installed motherboard.
One of the random goodies included with the Define R3 is a fan speed controller. With the use of the included splitter, three fans can be controlled. The controller can be installed in any of the expansion card slots on the case (pictured is the controller installed in the bottom-most slot).
Also included is a front plate for the 5.25" to 3.5" drive adapter, power and splitter cables for the fan controller, and various screws/standoffs/ties/thumbscrews.