No Bob this is not the butterfly coil. I haven't been able to get one of those to test yet. This is a 10" round DD coil. For some reason the 10" is not listed on all the pages.
The 10x12 SEF is a bigger coil and should be even deeper.??? On this one I can't personally say. This 10" will replace my stock coil and 6X10 coils. I don't see a need for them anymore. I will keep the 10" on the detector 90% of the time. If it gets trashy I'll use my 5" or maybe the new 6". If I really need to get deep maybe the 10x12 ( again on this coil I know nothing).
Where the 10" fits.
1- Its about 1" deeper than the 9.5.
2- Its DD footprint gives me more coverage and I don't need to overlap as much as the 9.5.
3- It is about 1.5 to 2" deeper than my 6x10.
4- It seems to separate as good as my 6x10 on multiple targets.
Now this part is just my humble opinion; Several people have said the 300 coil has been a bust. Not that it isn't a good coil, for most hunting it is too big and is overkill. On another forum, ( I can't post to other forums here) Carl@ Whites said Whites will be coming out with a new 10" coil soon. Soon, IMHO, I think you will see Whites shipping new MXT detectors with a 10" standard coil, no 9.5 or 300. Rob