The dims on this board are 7'2 x 21.25 x 2 7/8. I've been wanting to build a channel bottom for myself for awhile and decided to give it a go. At their deepest, the 4 channels are about 3/8" deep. So far the board paddles and surfs well. Looking forward to testing it in some juicier surf up north in a few weeks.
Bottom shot
Channels/fin array
Deck shot with me in it for size/perspective