As the water gets deeper, you may want to change the length of your jack pole as you go. This allows you to connect two pipes together to make the length you need.
The shorter jack pole is more stable in shallow water than a tall jack pole. This part also allows you to fit your dock tools into a small car.
To avoid confusion when buying pipe that fits in this, the industry standard calls the pipe size as 1.5″ schedule 40 but the O.D. is actually 1 7/8″.
This clip features a jack pole and leveling winch being used to support a dock section while the legs and feet are installed in the corner sockets of the dock frame.