The LACEnano tattoo machine is a rotary machine because it is driven by an electric motor (a brushless one). But it feels much more like a coil machine because the drive system is magnetic like with a coil machine and so it has the same kind of give that a coil machine has. As you know coil machines don't work very well with cartridge needles because the simulated give mechanism in a cartridge (the rubber or metal spring inside) works against the natural magnetic give of the machine. It is the same with the LACEnano and so we only recommend using classic needles with it, no cartridges!