They made a few small changes to the ceramic/silicone piece and to the metal casing. Here's a picture of the newest style atomizerthis is what the old style atomizer looks like
I recently bought a Persei and I absolutely love it..and now all my friends are going to buy them. I I have two questions . What batteries do I use to get 4.3-5.2 volts. Second after using the Hercules I noticed it was leaking lots of oil. I is this normal?? I've attached pics.