Usage The first parameter specifies the gauge:   →   Most existing rail gauges can be entered by their definition using units ,  or .  Spaces are allowed (both  and  are valid). Sizes can be decimal (like , , ), but not in fractions (). Using a thousands-separator is not possible ().  The names of some twenty rail gauges are recognised, and can be used:   →   The template is case-insensitive (both  and  are OK). Standard gauge even has abbreviations like . More on this below   Basic input examples Parameter input Result Note     standard gauge     standard gauge     standard gauge     standard gauge, this way imperial units first      is recognised, but not many more in . Better use      HO scale model railway     Miniature railway     Brunel gauge                 Input not recognised (so no metric value), output copies the input     Input not recognised (so no metric value); output copies the input. This is a good way to enter an uncovered rail gauge on a page: other editors will notice (and can add a new gauge to the template!).   When an input value is not recognised by the template (see last two table examples), the template simply returns the input as it is: {{RailGauge|14in}} →  The page with this unknown input is also listed in a maintenance category, in the background, that signals interested editors that there is a new rail gauge used in Wikipedia. More on this below.  Some gauges in metric are defined in metres:  is recognised. However, it is not available for all metric defined gauges. Using  is a safer bet.  Allthough some gauges are recognised without a unit ( meaning ), it is advised to always enter units. This will prevent confusion.  All input options   For a more technical overview, see .  Optional parameters {{RailGauge | | al=on | allk=on | disp=s, 1, or | first=imp, met | wrap=y | unitlink=on }}   Optional parameters Parameter What it does Example (code) Example (output) al=on Adds the alternate name after the gauge measurement values {{RailGauge|sg|al=on}}  allk=on Adds a wikilink to the alternate name where applicable {{RailGauge|sg|allk=on}}  first=impfirst=met Puts the requested measure first (metric, imperial) {{RailGauge|1000mm|first=imp}}  disp=or Uses an "or" as a separator rather than parentheses {{RailGauge|sg|disp=or}}  disp=s Uses a slash as a separator rather than parentheses {{RailGauge|sg|disp=s}}  disp=1 Only shows the first measure (may be used when repeated on a pageor in conjunction with first= to display the output only) {{RailGauge|sg|disp=1}}  wrap=y Will allow the output to break before the parenthesesif column width is narrower than output {{RailGauge|sg|wrap=y}}  unitlink=on Adds wikilinks to the measurement unit labels {{RailGauge|sg|unitlink=on}}  Gauge color key The colors below are used as legend colors for specific gauges  Maintenance categories Sometimes an input parameter is not recognised by the template (that is: it is not defined in the internal list). The article page with this {{RailGauge|some unknown gauge}} is added to a background "maintenance category" (named :Category:Pages with incorrect use of RailGauge template). Interested editors will check that category. they can, edit that article page (for a spelling error), or propose to add that rail gauge to the template.  There are two categories under :Category:Wikipedia rail gauge categories that can help in maintenance of the template.  :Category:Pages with incorrect use of RailGauge template: input to be checked. No error message on the page, but it needs attention.  :Category:Pages with no gauge entered in Infobox rail line: template  is used, but parameter  is empty.  Technical background This template uses the Lua module Module:RailGauge to format the gauge data. The data itself is stored at Module:RailGauge/data. Please see the /data subpage for information on how to add new gauges.  TemplateData  Sources  List of scale model sizes  Rail transport modelling scales   Light Rail Transit Association (LRTA)  Latin America is very well covered   UK based, covering most countries  Scaled rail models  References