It's big, i can't tell you exactly because it's still in original package - this is from cabelas web site:
The Super Magnum Bag holds twelve 3700-series adjustable utility boxes. It holds one Cabela’s 3600 box in the front pocket and one 3600 box in each of the two side pockets. Two specially designed Storm-Proof external pockets for your camera, cell phone, GPS or VHF radio. Four external pockets, including three large mesh pockets.
Dimensions: 27"L x 14"H x 12"D.