Nissan Turbo Identification

[R31Heaven]

How do you tell the difference in Nissan Turbos? I was looking at a site the other day and there was a picture stating that he had two RB20det Roller bearing turbos one was identical to mine it had marking 16V on the front and the same style actuator. What confuses me is my RB20det (Red Top NICS)is suposed to have a ceramic non ballbearing turbo. How do you actualy tell what type you have with out pulling the thing apart? Is there a list of model numbers? any info would help.

thanks