Bdc or bvc how to tell

[Swamprats]

I get the fact that the bvc for the nautilus and mini is the way to go. My problem is I need to know how to tell them apart. The folks at my local vape shop don't seem to knowledgable and just keep selling me nautilus replacement coils. How can you tell them apart. It might be asking a lot but a side by side photo for comparison would really help.

 

[DetraMental]

With the BDC you can see the coil wrapped around the wick, it lies horizontally. The BVC is covered by a silver mesh on top so you can't see the internal workings.