It's a keylock oval. These work great for racking nuts snag-free and are solid as a carabiner brake in a pinch. I don't aid climb, so I can't speak to their performance there, but for my purposes they're great. The gate has an angular grind on the inside opening end that lets it eke out an extra mm or so of gate clearance (see picture). Overall a functional, beautiful and solid piece of gear. My go-to oval.