Kinda figured...the black buttons are the older style buttons. Sometimes massaging the button lightly will get it back to working again. I have not had any issues, but I am real gentle in pushing those buttons too. Just enough to get them to activate
At any rate, the volt batts are great too, and as I said, they will work with the V4L equipment. You will notice a difference though if using the V4L cartos on the batts. They are very very similar to the Bloog Batts and if you check out Morandirs Blog, he did a comparison of the 2 lines. Each works best with their own cartos/batt combos. They will still work, it is just a voltage issue between the 2. You will find a bigger difference if you are a wow cart vaper, as opposed to the cool carts (which is my personal preference
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