D4V2 E21A and 219BT-V1 differences

I am going to order an Emisar D4V2 and I like a tint of 4500K. What are the differences between the E21A and 219BT-V1 emitters ? From what I can tell the E21A has no dome and the 219BT-V1 does ? What emitter is more favored with people who own a light with them ?
Thanks for a reply

I don’t know why I couldn’t find that. Thank you.

You're welcome :-)

The E21a is less pink, they both have essentially the same output.

I like the more pink tint of 219b better…

example of the difference
the light on the far right is 219b 4500k. the second from right is similar to the tint of E21a 4500k:

Thank you Jon The 219b does look the best !

Why is the 519a also known as the E21a?

It’s not.

It isn’t. Two different LEDs.