Like most nuts, but what you don't see in the picture.
What you don't see in the picture is that this type is splined but for safety reasons a spline is missing. This means all your other slotted chucks will not fit this nut.
Pros
seat type seat flare nut; thread size M12 x 1.25; overall length 1.24; hex size 13/16; Includes 4 lug nuts