Internally Threaded Belly Button Rings with Red Double Gem. The internally threaded belly button rings offer a design that is more comfortable. The internally threaded belly button rings makes it easier to insert and remove this double gem belly ring from your pierced navel. Less irritation and less frustration and great style. The internally threaded belly button ring with red double gems give you the fashion you want with the comfort of a smart design of the internally threaded barbell. 14GA. 7/16" barbell. 5mm ball top.