Hi mmohamed2, if you connect your Adata hd650 external hard drive and check device manager/disk drives or use other utilities, you can probably see what brand and model hard drive is inside to check the specifications which hopefully can be found online.
Assume you don't want to remove the hard drive from the Adata hd650 external hard drive housing yet, but if you do, you can also just measure the height with a metric ruler to check the thickness too.