If you want to lock your oars into your tender when you leave it, here’s an idea. Use a piece of stainless steel strap, bent into a U shape to fit an oar inside. drill a series of holes down one arm of the U, and route two slots in a thwart. The U piece then fits around the oars and through the slots in the thwart. You can then put a padlock through one of the holes beneath the thwart and the oars are secure! Just don’t lose the key…