The first 27 upgraded VIRM-1 trains started running in the Netherlands in 2017. NS will be upgrading a total of 80 trains with 415 coaches in the period to 2020. Sustainability is an important factor here. Some elements, such as the cab and vestibule, are to be reused as much as possible. LED lighting that adapts to daylight levels will be added. The trains also have energy-efficient climate control systems and eco-toilets with bioreactors. The train setup is changing too: the upper deck is suitable for reading or working, with seats in twos and business-like decor, and there is more space for luggage. The lower deck is becoming more informal, with seats opposite each other and a lounge seat. Studies show that passengers find the train clean, tranquil and light. At the end of 2017, it was decided to upgrade the VIRM-2 and VIRM-3 type trains as well. The design phase has started and the first train set will be completed by the end of 2020. All SLT train sets will have an environmentally friendly toilet and retractable step by 2021 at the latest.