The Dotmod DotAIO Coils are designed specifically for the Dotmod DotAIO kit but are also compatible with some Nautilus tanks. The coils are constructed from brass and come in three resistances: 0.3ohm with a recommended wattage range of 20-35W,0.7ohm with a recommended wattage of 14-20W, 1.2ohm with a recommended wattage range of 10-14W.