Imagine it upside down from the picture. Then sliding it onto the top of a FEL bucket, tighten the bolt so it don’t slip off. When adding chain tension on an angle, when lifting or pulling with tractor, it will “pinch” itself against bucket and not allowing slippage until bucket lip begins to bend under pressure. Seems like a good idea if you don’t want to do any weld on hooks. Weld on would be much stronger because they are typically on rear (top) of bucket. I’ve never actually seen these before, so I’m speculating based on observation only. Hopefully someone will post with actual experience with these hooks.