How to Open the Apple Remote

I think is a stupid thing but i spend many hours to try to open the apple remote for changhe the battery or only for have a lokk inside..
i try many different thing and in the end i open it whith a knife..after i had open it i found the correct system...

Put the bottom of the remote up, find a little circle on the plastic and push it whith a pen or a little screwdrive..
is very more simple to do then to say...

Now change the battery o simply have a look inside..

bye thank's for the time...