The horizontal spacing of the vertical rows of holes is specified by EIA-310 at 18 5/16″ (18.312″ or 465.1 mm). However, many manufacturers use equipment mounting slots instead of holes to allow for variations in this dimension.
![Support call center agent](https://dl4jz3rbrsfum.cloudfront.net/images-new/general/callcenter.png)
Questions?
Talk to a specialist
1.877.297.6937