The Stonehenge atty is a monster at 30mm with 6+mm juice well and 5-post design with removable rings for standard building area. The huge well allows for lots of cotton and juice so no there is no need to drip every other vape. The post holes are 2.5 mm in diameter and the center post is 3mm in diameter which allows for quads coils with up to 20g wire. The center post is solid copper with a peak insulator, which allows for maximum conductivity. This is an atty designed for low ohm or series style builds with monstrous airflow for advance coiling and vapor.