The Harmony Super sponge will help keep the inside of your boat dry. This synthetic sponge has a cellulose cover, absorbs up to a liter of water, is resistant to mildew, and is machine washable. It's durable, compact and features a handy tie-in tether sewn to the corner. It can be used in conjunction with a bilge pump on on its own.
Most durable sponge with its cover.
I bought a cheep auto cleaning sponge for my white water kayak a time back. Soaks up a lot of water fast. Can even bail my ww with this. Just purchased one of these type. It will hold a lot of water as said. But if you are needing a small bailing job. This sponge is very, very slow to absorb 1 sponge full. Not at all good for larger amounts of water. It for sure is a nice texture and has tie string. So far for me and my needs. I found a much less advantage with this one. So back to my cheep auto sponge. Or possibly purchase a pump, to go along with this cleaning sponge. Just would depend on the size for your boat.