I don't believe I've ever used the type of ring shown, so perhaps I'm completly wrong but I suspect the idea is that the offset internal hoop is used to force the ring over to one side. In other words, since the hook is on one side of the mast, the idea is to get the ring shifted over to that side of the mast to make it easier to hook. That said, when you initially set the thing up, you have to make sure that when the shackle is connected to the sail and the knot is facing away from the mast, the ring will be forced to the hook side of the mast (i.e. the knot faces away from the mast and is on the non-hook side of the mast). Again, I've never used this ring, but this would be my assumption. Personally, I use a plain ring with just a small hoop on top for the halyard, the shackle is not welded to the ring- it works fine on my TheMightyHobie18 and H17. I think the biggest trick to getting the sail down is 1) make sure the boat is into the wind. 2) make sure you keep the mast rotated until the ring is below the hook.

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