I have a horrible feeling this may be a real dumb question....

Have an Acer Aspire 4520 that has an ExpressCard slot,  first time I have seen one.

It seems to have a cover over it that is sprung, you can push it in a we way and it springs back, a bit like with an SD card etc but it doesnt spring open, just back to its usual position.

How do I open the darn thing ?