broke off a toothpick in one of the 2 airholes on my vivi nova ( think that means its a v1 as v2 and up have the air holes in ventral tube or w.e) anyway all joking aside about this being my first mod. it actually makes a huge difference !. the vivi nova with airholes on the base are way to airy a draw for my liking. simply blocking one up makes a much tighter draw. sucess!