Due to the geometry, these rings are marked TOP, indicating that they must be mounted to the pressure side. The initial surface of the piston ring that touches the cylinder wall during installation is small. The pressure between the ring and the cylinder wall will provide a counter-pressure to the pressure behind the ring. The ring can run in slowly and ensure that the other piston rings can do the same.
In the DIN standard 34111 this type of ring is called M-ring. This is especially true for automotive applications.
The examples shown only represent some of the possibilities. Euroring will happily discuss the best installation with you for your specific situation.