The EW I & II Wagons were once the backbone of the SBB fleet, with over 1000 produced of the EW I wagons alone. EW stands for Einheitwagon - which roughly translates to standardised wagon. These could also be seen amongst private railways in Switzerland such as the BLS and SOB. Even the narrow gauge railways had their version of this wagon.
There are still some of these in use today, but they have been successively scrapped over the last few years. The wagons I present in this film are the grey - blue - green wagons with yellow doors, also known as "Papagei" - Parrot. They all required a conductor to be on the train during operation because the doors didn't have obstacle detection. In 2015, all wagons were taken out of service due to a requirement the department of transport introduced, requiring trains to be equipped with an override button for the emergency brakes.
If you have any questions, feel free to ask.