Figured to share what I found that works really well. The problem I've had for so long was the cotton creeps in around the coil and slows the air flow to the point where the hit sucks. I was ready to give up re-building the throw away stock coils until............. I recently got these notch coils from Fast Tech. $2.60 316L Stainless Steel Notch Coil Wire for RBA Atomizers - 0.5ohm / 10 pcs at FastTech - Worldwide Free Shipping The above are .5 ohm. Below are .2 ohm. $2.82 316L Stainless Steel Notch Coil Wire for RBA Atomizers (10-Pack) 10-pack - 0.2ohm at FastTech - Worldwide Free Shipping I was concerned about the size Fast Tech descripts them to be, 5mm round, 8.7mm in height. Well they work perfect. These are the key to fixing my air flow problem. They work very well with the stock beast coils as well as the melo 2 coils. Any stock coil that have the 3 to 5 mm positive pin, and these notch coils will work fine. As for the Kangertech coils with there positive pin at about 2 to 3 mm wide, NOT SO GOOD. But all the bigger/fatter coils fit the notch coil very well. Cotton wraps around the coil with no issues. They fire up nicely and last longer then my wire build coils. At .28 - .26 cents a coil, I'm a fan.