British N gauge is a model railway scale and gauge, rolling stock is to a scale of 1:148,[1] track is 9 mm (0.354 in) width as with all other N gauges making track and rolling stock approximately 10% out of scale with respect to each other.

When N gauge was developed it proved impossible to fit the then available motors into scale models of British prototype locomotives.

British railways use a smaller loading gauge than those in Europe and America, resulting in smaller locomotives.

A greater body size was required on the models to accommodate the motors, so instead of adopting the correct 1:160 scale, 1:148 was used.

A similar problem and solution was adopted with OO gauge and British TT gauge in Britain.