Titanium Internal Labret with Disc - 1.2mm (16G)

These work well for lobe piercings. I ordered 8mm posts, but 6mm would have probably worked just as well since there's some free space when wearing them.

Advantages: Flat backs means that I can't spike myself in the neck when I sleep.

Disadvantages: Flat circles aren't the easiest to hold onto for fitting when you're only able to see them in a mirror! If you aren't used to screwing in the fronts of your earrings, either get a disc larger than 3mm, or get a shape that isn't totally round so you have some more grip.