The Artery PAL 2 Replacement Cartridge is the proprietary cartridge that has a juice capacity of 3ml. Juice enters the PAL 2 through a silicone stopper located on the middle of the device. The coil enters from the knurled bottom; located on the knurled section of the pod is a 5mm by 1mm airflow adjustment ring. The PAL 2 pod does NOT come with a replacement coil. These replacement cartridge are designed for MTL style vaping, respectively.