In any piping system there are always points to interface between:
- 2 different pressure ratings
- 2 different pipe sizes
- 2 different end connection types
...and some times, all three interfaces together!

Interfaces may be a critical and conflictual issue when it also interfaces between the scope of supply of different companies.

Range:
It is essential before you buy a crossover (or X-over) to specify and anticipate all interface points you may need before starting a piping installation.

The following specifications shall be given:
- fluid service (Standard, Sour gas, chemicals, etc.)
- fluid & ambient temperature service
- pressure ratings of both sides
- both sides connection types and sizes
- reference codes and standards

A crossover pressure rating is always the lowest rating of the two piping systems (or equipment rating).

Norms :
- NACE MR 01-75,  AINSI B16-5, B31-3, API 6A.
- PED and CE compliance on request.
- Other standards on request.

Construction:
- Buttweld ends.
- Threaded assembly.
- Integral machined.
- Material per fluid service (carbon steel, stainless steel). 

End Connections & nominal size:
- Hammer Union.
- REGO^® Union.
- "Grayloc^®" type Hub.
- Flange ( ANSI B16-5 or API 6A).
- Todo^® Union.
- Guillemin^® Union.
- Kamlock^® Union.
- Threaded Ends (NPT, LP, other threads on request).
- Common sizes up to 6".

Special requirements can be provided such as:
- ported crossovers.
- manufacturing to a required bore or special I.D.
- special flow direction.
- multi-direction flow (more than 2 ends).
- Etc.