 you know somebody's on a wakeboard whatever else in the water it's very important to let somebody else know so that they're not running um wake towards you or that they're not getting too close behind the boat and then especially when that uh border skier eventually goes down as they all do uh you can wave that flag up and make sure when you're stopped that nobody's um coming too close to you and um pretty much everybody that's out there driving a boat on the water