Take a Four Socket Cross (685-804HC) and attach a 12” pipe to each open vertical end then tighten set screws.
Slide a Double Tab Offset Flange (689-804HC) onto each end of 12” pipe. Make sure the Double Tab Offset Flanges (689-804HC) are flush with the end of 12” pipe then tighten set screws.
Stage 2
Attaching Base and Vertical Seat Support
Slide your 12” pipe, with the chair spring installed, and slide it into the vertical hole of 18” pipe then tighten set screw.
Attach the Double Tab Offset Flanges (689-804HC) to the surface you plan to use and install using nuts and bolts for strength and durability.
Stage 3
Attaching Seat
Install the boat seat into 12” pipe.
This is a standard boat seat and the peg that came out the bottom of the chair fit the 3/4” pipe perfectly.