StLB is looking to purchase seven trains with an option for up to eight additional sets as either multiple units or railcars with trailers. The maximum speed of the new vehicles should be 90km/h and the trains should have capacity for 100 or more passengers. At least one of the two or three-car sections must be low floor.

The railway is also open to several options for the trains’ power supply: electric via catenary with backup batteries for the non-electrified tunnel sections; electric from batteries, which are charged at the end stations and on short sections with catenary; and hybrid systems using either diesel or hydrogen fuel or engines powered by LPG.

The market research initiative will conclude in spring 2019 with a final decision on the drive concept taken in the summer. A procurement procedure will then ensue with the contract set to be awarded in summer 2020.

The Styria provincial government confirmed in July 2018 that it would proceed with a plan to modernise existing infrastructure rather than convert the Mur Valley line to standard-gauge. The procurement of new rolling stock is part of this plan along with partially realigning the Unzmarkt - Murau section, which will reduce journey times from 38 minutes to 25 minutes.