NMD's Reversible boardbag is the first bag that can be used as a double & triple bag.
When used for carrying boards this can fit 3 x 45"  boards, Unzip & reverse & it will accomadate 2-3 boards with 3 external pockets.

 

Note: The NMD Bag will fit 2 boards plus clothing etc in internal pockets with the backpacks/ shoulder straps on outside as board shown in first few images.
*You can fit 3 boards this way also but there is not much room in internal pockets.

If you reverse it ( you can also reverse back pack. shoulder straps) You can fit 3 boards internally but the internal pockets only have one zip so would not be lockable this way.

Fully Padded with more features than a swiss army knife. Much R&D has gone into this genius bag

Features:
3 Internal pockets pockets for Fins, Wesuit, Towel and anything else.
Reversible Hand, Back and Shoulder Straps
Fully padded and reinforced.