Originally Posted by sethro
I couldn't find any really good pics, just this crappy one on my phone. It is just 3" PVC with an approximately 1" slit cut in the back from the bottom to about half way up the pipe. It fits pretty tight so there is no slop when installed on the post. My docks are 8' long, which works fine for any Stars and Stripes that show up at the dock. Works even better for bigger boats, but if I was designing a bumper system I would space them about 6' apart.
I use a dock like this is the summer at a friends house. They did it a little different in that the poles with the pvc are seperate from the dock poles. They then bungee the top of the pole/pvs to the dock pole to give it a little slop to lessen the impact on the dock as well as on the boat.