Car Seat in Spain

[orval]

We are heading to Spain next month and Google has not given me a definitive answer.  By chance, does any one know if my 8 year old who is approx. 131 cm tall needs a car seat?  I have read he doesn't need one if he is 135 cm but also some conflicting info.

Also, what kind? 

Some sites say he still needs the harness, some just the booster using the car seat belt. 

[frlcb]

This says 135 cm

en.aurigacrown.com/blog/car-seats-spain/

Also he would be in a booster