XC60 Momentum sim holder
 

First question, Is there one? Second question what is the purpose of the small slot in the panel holding rear and front widow heaters and radio off/on switch.
Nobody seems to know around here!

Evening
This part of the forum is a pretty dead end so no-one looks here - next time try posting in the main section one level up.

Ok, so re your two questions:
1. If your model is equiped for a SIM, the SIM Holder will be behind a small black plastic cover that levers carefully out found low down in the Passenger Footwell. A common problem with users is that as they replace the Sim Holder/Sim for either the Sim &/or Holder to fall down behind the carpet which is hard to retrieve unless you have small hands - be warned.
2. That small slot is NOT what you are/were thinking, the amount of times users post queries as to why their Sim will not fit.........In fact the slots real purpose is to act as a grill to hide a Sensor behind - I think either Temperature or Air Quality!