... special apparatus, can reach 10 meters underwater.2) Service Life: the design life of two years, but ... as long as 10 years, but the proposed one-for five years to prevent aging.3) The ... difference in water pressure automatically turn on and off, safe and reliable, no noise, no need for ... ) Anti-corrosion, adaptability, and long service life. 5) A wide range of sizes and nominal diameter DN50-DN2400. The ...