2 gauge

Gauge 2 is a model railway gauge, originally, then standardised in 1909 at, a 20% reduction and a change in definition: from mm to inch. It has since fallen into disuse. The gauge was introduced by Märklin at the Leipzig toy fair in 1891. Gauge 2 was equivalent to a 1:22.5 scale.

Related scales and gauges

After the change to in 1909, gauge was standardised as 3 gauge.
European G gauge trains are built to the same II gauge scale, but with a narrow rail gauge of . This G gauge at 1:22.5 scale represents narrow-gauge railways. This scale-gauge combination is sometimes called IIm in European literature.
In the UK, Gauge 2 was 2 inches while Gauge 3 was. From this, it follows that G gauge is sometimes, albeit rarely, referred to as 3m. A 2 inch gauge of standard gauge locos gives a scale of 1:28.25, not so far off the 1/29 used by some manufactures with gauge track. In the grand tradition of model rail gauges often being narrower than the full scale equivalent this is deemed perfectly acceptable.