This one of a kind cartridge is well constructed from top grade, quality materials making t both durable and long lasting, surviving daily use. More advanced than traditional cartridges on the market, the Atmos Optimus Replacement Cartridge incorporates a unique measuring scale that allows the user to see the amount of oil remaining in your cartridge. The exclusive heating element in the chamber heats your oils evenly and neatly for smooth, refreshing draws. Featuring a bottom coil, top fill design, the Atmos Optimus Replacement Cartridge is an instrumental accessory for endless enjoyable sessions. Make sure to get one today!