I'll second the recommendation above.
After we installed a tower on our boat, the angle of our existing whips made docking very difficult. After gulping a few times at the price, I purchased one of these bases for the outside whip (the whip closer to shore stays in the bow area so I only needed one)
Once the tension is removed the whip springs back to an almost vertical position, allowing the boat and tower to pass by easily.
http://www.overtons.com/modperl/prod...view&from=grid