American OO scale
# American OO scale

American OO scale is a model railroad standard that has a scale of 4 mm to 1 foot (1:76) and utilises 19 mm (0.748 in) for the standard gauge track.

The standard is different from British 00 gauge (which is popular in Great Britain), as it utilises 19mm gauge track rather than HO scale 16.5 mm (0.65 in) gauge track. It also differs from British 4 mm finescale standards (EM gauge and P4) which have gauges of 18.2 mm (0.717 in) and 18.83 mm (0.741 in) respectively.

