I can run 1.5ohm dual coil on both my provaris at 4.2v but it really drain the battery fast I think I'm better off running 2.5ohm dual coils less strain on my battery. my lava tube wont go higher than 3.64v with the same 1.5ohm carto. it's not a big deal for me because like I said it just drains my battery really fast and I can get more watts out of a 2.5ohm DCC and I'm still deciding if I like the DCC anyway