Well, it's not a machine I would have picked, but it has a regular 510 pin connector so it should be fairly safe using just about any topper without risking a dead short at the connector. You can not use Ni or Ti coils with it, but Stainless, Kanthal and NiCr should work just fine. If it were me, I would not put a coil on it lower than .25-.3Ω. The machine is a pure mech mod with fixed batteries. That means several things: Since the batteries are fixed, you have no way of knowing what actual batteries are in it, and therefore what loading may be safely put on it. It means 4.2V is the maximum, but voltage (and thus watts applied to the coil) will drop with every puff from 4.2 down to wherever you charge it again; the machine turns the LED red at 3.65V from what I read. Since it's a mech, and the voltage is therefore (semi) fixed, the only way you can adjust wattage is to change the coil in the topper. It is not the kind of machine I would use with a prefab coil tank. It will work, but it can be pretty frustrating unless you just happen to have a tank that offers coils at the exact resistance you like to make the vape you want. The flexibility of making your own coils is something I think of as a requirement for mechs. Use the
Ohm's Law Calculator to figure out your wattage: at 4.2V, a .25 coil makes 75 watts; a .4 coil makes 44 watts; a .7 coil makes 25 watts; a 1.0 coil makes 17.5 watts and so forth. Bear in mind those wattages will decrease as the battery voltage drops.