[k20em2]

I recently bought an a/f sensor from an rsx-s. How can I verify that I got the right one and not the secondary sensor? Would the part number be on it?

 

[supafly]

there should be a 3digit # on the part that the socket will go on to to tighten it.

I believe it is 106 or 109..... this is prim O2. also it is a little longer than sec.