Mine came with an insert for the CH can. However, the thing does not hold very well mechanically. I have to be very careful when unplugging it. CH plug connection is mandatory, if not there, contact Digitec Suport.

I currently have 4 WD MyBook in use. All of them came with a two-pin power supply (suitable for Swiss sockets).

The power supply unit was still included with my "My Book". That's no problem. The operating voltage is certainly stated in the description. You are well served with a universal power supply unit with a Swiss plug.