The D3•Hover combines a CS3 as a wonderfully slim module for drones, along with the Pack Cap Rear to allow the bag to be configured as a backpack for those times when you need to fly and be on the move at the same time, and of course, the Pocket Cap Front for all the small stuff.
NOTE: This price DOES NOT INCLUDE ANY FOAM. This bag is configured with no foam, so you'll have to add either the Drone Foam for the DJI Spark, or the Drone Foam for the DJI Mavic Air, since these are the two foam sets designed to fit inside the CS3. The D3•Hover Bag consists of a CS3, inside which you will place either the Drone Foam for the DJI Spark or the Drone Foam for the DJI Mavic Air, and of course the Pocket Cap Front to organize all the additional small stuff that goes with being a Drone Pilot, and finally the Pack Cap Rear, which gives you the ability to quickly turn the bag into a backpack.
The D3•Hover also includes a Main Handle and a Shoulder Strap. (Most of the time, it's nice to keep the backpack straps stowed away and just use the Handle and the Shoulder Strap.)
Because it is possible to build larger configurations that combine multiple Center Sections (most of which include the CS4), and because the CS4 opens to the front, and because this CS3 is often zipped onto the back of a CS4 in larger configurations, this bag (the D3•Hover) opens towards the rear.
As with any BrightLine Bag, the FLEX System lets you add other Center Sections at any time to build larger bags to serve all sorts of needs, as your gear requirements change from day to day. This bag (the D3•Hover) is an awesome small starting point.