The railroad "code" indicates the rail height in thousandths of an inch. The help regulate the sizes and scales of your model train accessories.
Examples of this railroad code include: Code 100 (.100"), code 83 (.083"), and code 70 (.070") are common sizes in HO scale while code 80, code 70, and code 55 are used for N scale.
These sizes represent the various sizes real railroads use.
Code 83 has a rail height of .083"; the products in this category below include both HO scale code 83 products.