An earring thread or threader is made of chain and fits through the earlobe. So, this chain portion here, is the part that goes inside the earring hole. And, the solid piece makes it easier to pass through the ear. Now, the little loop on the front is where you can attach a dangle. And, you want to be careful about weight and balance with these types of earrings because very heavy things on the front of your earring can pull it down and out of the ear. So, you’ll want to pay attention to that as you’re designing. There are also some differences with different styles Some types have an arch at the top like this gold-filled piece and the sterling silver piece here. The arch is the part that fits through the hole in the ear in this style of earring. And then the dangle is suspended down below with more chain and the solid piece hanging down from the back of the earlobe. There’s also a style that has a loop attached to the arch and there you can attach your dangle. And, this is going to be a little bit more secure because it won’t pull through the ear. But, you’ll want to experiment with the different types depending on what you’re attaching to that front loop.