Had to mount them with screws instead of the usual clamps on both sides of the devices that spread when the screw is tightened and press against the box to hold the device in.
Are clamps (claws) still used in Austria? They have been cancelled on the latest generation of devices here. This could cause problems with old screwless boxes. (For the non-Europeans: Old boxes are just plain round tin-cans without holes for screws.)
At our school I remember many many receptacles hanging loose because everyone just ripped out the plug without holding the receptacle.
Many many? Having to hold the receptable??? That sounds like poor quality.
