Hi John,
414eb nylon/414eb brass ring
"other then opening them up, how can you tell when surfing ebay for them?"
Sometimes you can tell the difference if there is a good photo of the capsule through the grill.
You can see the white nylon ring, or the brass surface with the little screws going around.
I have been able to tell, sometimes not.
Careful with this --as some other capsules have the screws also -you can spot some pelusos as they are bigger in diameter..(I was temporarily had on this once myself)
thanks j