Difference between vr3131 - sa3131 - 3135

[aaaa89]

I am looking to understand the difference of these movement.
I am trying to understand which one is the best and which one have the antimagnetic cage.
I ask to trusty time to have a 3131 movement and they propose me the 3135... what is the difference? has it antimagnetic cage?

Awaiting someone who can explain me.

Thanks a lor

 

[Feefo]

Have you looked in the tech section. There's a whole subsection on movements there, and the Rolex section has a specific thread on Rolex rep movements

 

[aaaa89]

Have you looked in the tech section. There's a whole subsection on movements there, and the Rolex section has a specific thread on Rolex rep movements

thanks