Leon explains: Preventer on a sail boat 

Thanks, very clear on your arrangement. A couple of comments. Always best to lay off the boom as much as possible. This gives less chance of an accidental gybe. (Which is why I don’t like swept back stays) Of course then you have the issue of the sail rubbing against the shroud. Especially if fully battened. In this case you can rig a lazy main sheet, attached just behind the shroud, thus the sail can be pulled flat and off the shroud.

This info is just what I needed to rig my preventer lines. Thanks for the clear explanation of how you run the lines along side the boat.

Nice clips under the boom to hold the preventer line 😉

Nice setup👍 I use a beambreak. It is very effective as well.