how to change acer aspire s3 to ssd

I have an acer aspire s3 laptop.
although there's an internal 20gb ssd but I still want to change the hdd to a ssd.

after open up the back, I realize the internal hdd is smaller than normal 2.5" ssd.
so do i have to remove the box of my ssd to insert it or I need to get a different type of ssd for the s3.

thanks

 

What do you mean by smaller than normal 2,5" HDD. It is a 2.5" HDD as seen here.

Can you please elaborate and/or post photos? Did you mean the hight of the HDD?

 

maybe i'm wrong.
but does it mean I can just put a ssd like the link below into the aspire s3 without any problem?
Amazon.com: Kingston HyperX 3K 240 GB SATA III 2.5-Inch 6.0 Gb/s Solid State Drive SH103S3/240G: Computers & Accessories

thanks

 

I don't think so. The drive is 2.5" alright but its hight is 9.5mm whereas s3 seems to come with a 7mm drive.
So 2.5" SSD will be fine as long as it's 7mm height (there are plenty of those like Samsung SSD 840 among others)