Changes

[[File:Roadrailers_20180324.jpg|thumb|300px|right|New Former Rexquote Super Railer at Highley with No 489 behind (2018)]] The SVR uses Road-Rail Vehicles, also referred to as RRVs or 'road railers', for permanent way work. RRVs are modified versions of road vehicles, in this case excavators, which retain their normal wheels with rubber tyres. They are also fitted with additional flanged steel wheels which can be raised and lowered as required, enabling them to run on rails. The flanged wheels are free-rolling with propulsion on the rails being provided by the conventional tyres.