WBT NextGen RCA female w/Eichmann RCA male?

They do as long as care is taken to line up the Eichmann bullet plug side contact with the metal on the WBT NextGen female jack.

i had recently installed WBT NEXTGEN'S. i contacted WBT thru a email on this subject. they had emailed me back and recommended their rca's. i have used their's as well as eichmann's and others with no problem with at least making a connection and music playing. i guess if it connects and works then anyone's rca should would work with them.
their response was a technical one on why one should only use their's. i believe they were concerened with the way the other manufactures make their's, and how far the center post would push into the WBT'S female rca.

Thanks for the responses. I had read somewhere that the Eichmann male could do damage to the WBT NextGen RCA female?

I did some quick homework, and there apparently is an issue with the edges of the Eichmann center pin catching on the innerworkings of the WBT jack.

Here's the article written by Steve McCormack from "On Sound and Music". BTW, he seems to prefer the sound of the Eichmann bullets over the NextGen bullets.

Eichmann Bullet vs. WBT NextGen Bullet