My adult daughter is disabled. She must get a minimum of 32 ounces of fluid a day. Her staff are not good with keeping up. By giving them multiple bottles, they can now fill 4 of them a day with her favorite liquids and they can easily see that she must finish at least 4 bottles each day to get her 32 ounces. The cap access for a straw is perfect. My daughter also uses the ARK valves with her straws. All in all ARK has made it much easier to assure that she gets the fluids she needs each day.