Calibration gas standards

Columns

Fittings

Flow, pressure, and
on/off controllers

Gas purifiers
GC accessories
GC detectors
HayeSep porous polymers
Injectors/valves

Liquid handling
Portable gas monitors
Syringes
Tools

Trace gas analyzers
Tubing

About us
Photo tour
Upcoming trade shows

External unions

External unions have male threads, requiring a nut with internal threads. Bulkhead versions can be mounted through an instrument panel or on a bracket.

Note: Because 1/16" external fittings have very thin, easily distorted walls, they are not as durable as 1/16" internal fittings. We recommend the use of external/internal unions when connecting to an installed external nut.

Standard material is 300 series stainless. Also available in Hastelloy C and gold-plated stainless. Read about properties of metals.

Sizes available: 1/8", 1/4"

Product numbers

Select a type of union to jump to product numbers:

Standard
Bulkhead

Further reference

About unions
Internal unions
Standard
Bulkhead
External unions
Standard
Bulkhead
1/32" ultra low mass external unions
Microvolume unions
Nanovolume unions
External/internal unions
Reducing unions
Unions with 1/4-28 fittings

Standard external unions

Tubing OD	Bore	Product No.
1/8"	1.0 mm	EU2
	2.0 mm	EU2L
	1/8"	EU2T
1/4"	2.0 mm	EU4
	4.6 mm	EU4L
	1/4"	EU4T

Bulkhead external unions

Tubing OD	Bore	Bulkhead panel hole diameter	Product No.
1/8"	2.0 mm	5/16	EBU2L
1/8"	1/8"	5/16	EBU2T
1/4"	2.0 mm	7/16	EBU4
	4.6 mm	7/16	EBU4L
	1/4"	7/16	EBU4T