Definition: In the world of slot cars, HO Scale covers a range of slot car sizes from around 1:87 to 1:64 scale that run on small HO scale tracks. These slot cars are approximately 2"-2.5" in length.
HO is Half an O -- More or Less
The HO scale originated in the world of model railroad trains. The O scale or gauge is a size of toy train that is approximately 1:43 scale. The HO scale is about half that size. In model railroading there are more precise variations of the HO scale. In slot cars, the HO scale represents several sizes of slot cars that run on an HO scale track.
HO scale slot cars are popular in both organized competitive racing and home racing.
Pronunciation: [aitch-oh]
Also Known As: H0 (the "oh" may be written as a zero)