It's spendy -- $60 -- but well worth it. Simply put, it installs beneath the tone-arm travel, and when you hi the run-out groove, it triggers a little lifter. No, it won't turn off the turntable. But it picks up the tone-arm and gets it out of harm's way.
Here's a link. Their installation instructions make no sense, but fiddle with it, work the geomotry a bit, and you'll figure it out. Well worth the money and the effort!