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.
I needed something for bailing, but did not feel I needed a pump. These are covered and have an attachment so I can tie it to my kayak
This sponge did an excellent job of soaking up the water. I wish it just slightly larger but is fine as is.