N-Scale (N-Gauge)
N scale is a popular scale that is about Half of HO-Scale. Often this scale refers to a 1:148 scale with 1:160 (9 mm or 0.354 in) track gauge in railway modelling. The terms N scale and N gauge are often inaccurately used interchangeably, as scale is defined as ratio or proportion of the model, and gauge only as a distance between rails. The scale 1:148 defines the rail-to-rail gauge equal to 9 mm exactly (at the cost of scale exactness), so when calculating the rail or track use 1:160 and for engines and car wheel base use 1:148.
An advantage of N scale is that it allows modeling hobbyists to build layouts that take up less space than HO Scale because the models are smaller (by nearly a half) than they are in HO scale (1:87)