Very important when away from civilization, and the need to gather water is present. A water filter uses a carbon filter in combination with a pump made of differing materials. The impurities from water are flushed through and clean potable water is pushed through.

It is important to note that still-standing water is more dangerous, and a water filter should not be used on this type of water unless absolutely necessary. A water filter can be substituted by iodine tablets.