Doubt you'll find anything but 810 and 510 drip tips anywhere. Those are the standards and save for maybe a few ouliers like the stumpy. All the manufactures use the standard sizes.
I believe this originated before 810 was a standard. Early days of wide bore.
Early 2015 I think. I bought my clone in 2016 and I believe Element
mods had quit making them by that point.
I'm wondering if it may be possible to just use a 510 drip tip without the adapter by changing the o-rings out for thicker ones.[/QUOTE]
My measurement of the opening matches what I found in an old
thread.
"Hole in cap 11.5mm, ST is 11.3mm"
As I recall 510 tips are 9.5mm. that's a considerable gap to take up with an oring or similar.