Water Purification Sponge
Source Adventurer’s Armory
This fist-sized blue sponge absorbs up to 1 pint of water; squeezing the water out of the sponge purifies it, making it safe for drinking, washing, and similar activities. Filling and emptying the sponge is a full-round action. Each sponge can cleanse 25 pints of water before becoming useless.