Can I use 2.5 inch HD for Mycloud NAS if the original HD is damaged?

Can I use 2.5 inch HD for Mycloud 1 bay NAS if the original HD is damaged?

Not without modification. The circuit board is setup to be screwed to the current drive. With the smaller
disk not sure if the screws will hold the circuit board. Also the plastic case is designed to hold the disk
in place without screws.

I got you,
But from electronic and power delivery, is it okay?

I would think so.

Thank you