Manufactured in stainless steel or carbon steel as standard, Arkon flapper sight flow indicators are rated up-to***-bar pressures and up-to****-C temperatures. Especially suitable for full bore flows, either horizontal or vertically-upward. Ideal as a plant safety device where it is required to maintain a constant flow, such as lubricating or cooling systems. Available in sizes from ½” to 4” (6” and 8” on request). With connections BSP, NPT and ANSI**0.