These quartz nails are designed to rest in the top 14mm or 18mm joint of dome sets. They come for either 14mm joints or 18mm joints. They are extremely resistant to heat, and should never crack due to repeated torching. There is very little extra material on the nail head, and they heat up about twice as fast as glass or titanium nails. There is a disc around the middle with 4 cut slits for airflow and a nice cup on the top. The nails are about 2" from top to bottom, with slightly more than half of the nail resting inside the joint. Both sizes are currently in stock.