This removable chocks system will fit all shallow V boats (airkeel, airfloor wood floorboard or aluminum floorboard) up to 400 pounds including outboard. They come two chocks to a set with the pieces measuring 36 inches across, 6 inches wide, with a center height of 3 inches and an end height of 7.5 inches. Chocks weigh only 4 pounds each and can be used as a dinghy cradle or dinghy storage. The exterior fabric is SunBrella. Stainless steel female snaps are already installed to side tabs (one tab on each side). Male snaps must be installed on the deck. If you prefer not to drill holes on your deck, you can secure the boat to the deck (while resting on the chocks) using ratchet straps. NOT for submersible swim platforms as they are too bouyant. Chocks are available in white, light gray or special order black, dark gray, navy blue or red require two additonal weeks for delivery. See the related products section below for stainless steel ratchet straps (highly recommended as an added precaution).