Need help on which O2 Senors to purchase please

[KRAM36]

My car: 2003 Boxster S.

I want to replace both of these O2 Senors circled in red.



They are the oval plug connector type. Are they both the same unit?

My car has 4 O2 Senors per side and looking at Pelican for O2 Senors with oval plug connectors I get a bit confused as they show 1 Bosch (Before Starter Catalyst, Left or Right).

Then they also show the Bosch (After Starter Catalyst, Left or Right)

So which ones do I want to order to replace both the O2 Senors circled in red??

Porsche Boxster (1997-2004) - Exhaust Pipes, Manifolds & EGR - Page 1

Thanks!