-One Link valve for water and air-tight filling/draining. -Three 1 standard pipe fittings for the ultimate in custom installation flexibility. -Centered handle on top makes it easier to adjust the bag in compartments during filling/draining. -Weight label around valve for easy size identification. -Color-coded graphics for ideal boat location recommendations. -Sumo Sac spring-loaded Link Valve - Straightlines spring-loaded Link Valve creates a clean, water-tight seal that automatically opens and closes when the Uber or Sumo pump is used for filling and draining, eliminating water shooting into the boat.