I bought a military spec 5:11 Rush 72 backpack for mine. Its very tough, extremely water-resistant and just all around "Bad-***"..... I can carry my P4, controller & props along with my E-M1 and 3 lens, 3 liters of water and comfortably hike a 10,000 foot volcano. You'll have to customize the interior yourself, but, Drone World is using it as its "Ultimate Back-Pack" for the P4. Cut your own foam for it with an online service or do what I have, which is roll your P4 up in a beach towel and stuff it in there... (just don't forget and sit on your backpack during a break climbing your own mountain...)