Potable Aqua Water Purification tablets with PA+Plus lead the way in making small quantities of even the most bacteriologically questionable water suitable to drink. Iodine-based water purification tablets and PA+Plus neutralizing tablets. Wipes out bacteria and other micro-organisms such as viruses and protozoa found in unsafe water. Proven effective against Giardia Lamblia when use as directed. PA+Plus removes the iodine taste and color from water treated with Potable Aqua. For short term or limited emergency use only. Great for backpacking, camping, hiking, travel, and emergencies. Approved by the U.S. Environmental Protection Agency. Treats up to 25 quarts.