Horizontal pitch (HP) is a unit of length defined by the Eurocard

printed circuit board A printed circuit board (PCB), also called printed wiring board (PWB), is a Lamination, laminated sandwich structure of electrical conduction, conductive and Insulator (electricity), insulating layers, each with a pattern of traces, planes ...

standard used to measure the horizontal width of rack mounted electronic equipment, similar to the

rack unit A rack unit (abbreviated U or RU) is a unit of measure defined as . It is most frequently used as a measurement of the overall height of 19-inch and 23-inch rack frames, as well as the height of equipment that mounts in these frames, whereby th ...

(U) used to measure vertical heights of rack mounted equipment. One HP is wide.VME Dimensions; Eurocard subracks; VME.com
/ref> A standard

19-inch rack A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or ''ears'' that protrude from each side of the ...

is 95 HP wide of which 84 HP is typically usable. A standard

23-inch rack A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or ''ears'' that protrude from each side of the ...

is 115 HP wide of which 104HP is typically usable.

References

Units of length Mechanical standards Computer enclosure {{measurement-stub