"the product description does not state that there is no CH plug".
This is mentioned. In the specifications (you just have to read more than the description) it says:
"May be equipped with a power adapter: Yes".

But as a customer of a Swiss dealer, you have clear rights. You just have to know.

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Digitec (or any other Swiss dealer) is obliged to supply electrical appliances with a Swiss plug. If the appliance is supplied with a foreign plug, a suitable replacement cable should be supplied if the mains cable is pluggable or alternatively if the mains cable is permanently connected, a suitable adapter should be supplied.

If the appliance is delivered without a suitable plug, complain to the customer service and insist on a cable or an adapter, free of charge.

Info Digitec --> https://helpcenter.digitec.ch/hc...
Point 1 --> https://www.esti.admin.ch/de...

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There are fixadapters where an additional foam rubber washer is clamped between adapter and Schuko plug to seal the gap. Max Hauri fixed adapter (type C (CEE 7/17) contour plug)

For your second question, however, you are mainly responsible for a safe installation and operation. With a Schuko plug + corresponding fix adapter you are just as safe AND unsafe outdoors as with a proper Swiss plug. If you want to leave the Outdoor Light Strip permanently plugged in outdoors, the socket should be in a place protected from rain and moisture. The IP 67 rating of the light strip only applies to the power supply unit, the cable between the power supply unit and the light strip and the light strip itself. But not to the plug that is plugged into the socket where any cover is folded up.
Only with one of the new sockets and plugs according to the new IP55 specifications would you be really safe and somewhat better off.

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