You want to protect your favorite windsurfing board from the dings and bumps that go along with life, you need a Day Wall Bag from Epic Gear! With 6mm padding on both sides, these bags have enough padding for light protection without being super heavy and bulky. Nylon fabric on one side and solar reflective material on the other and a fin slot on both sides (so you can decide for yourself what is the top and what is the bottom. The plastic zipper won't corrode in salt air.
These bags are coffin style (with side walls), so when you are deciding what size you need, the width of the bag is the width of board that will fit inside it.