Aquatic Technology 8025WS2418E 24"x18" Yellow Water Uis Recirculated - Do Not Drink! Sign measures 24 x 18 inches, is printed on .040 mil Styrene Plastic, and is designed for safety reasons to advise patrons to not drink the pool water. Lettering height on sign meets California state code. Lettering height is 4 inches. Our Caution signs indicate a potentially hazardous situation which, if not avoided, could result in moderate or minor injury. This sign is lightweight, durable and weatherproof for indoor or outdoor use.