External/internal unions have male threads on one end and female threads on the other, for connecting a standard zero dead volume fitting to an existing tube which already has an external nut made up on it. Standard material is 300 series stainless. Also available in Hastelloy C and gold-plated stainless versions.
Select the union with the bore that matches the ID of the tubing. If the IDs are different, choose the union with a bore which matches the smaller tube bore.
Bulkhead versions are designed to be mounted through an instrument panel or on a bracket. The fitting body is undercut so that it bites into the panel when the mounting nut is tightened, eliminating the need for a lock washer.
Note: Because 1/16" external fittings have very thin, easily distorted walls, they are not as durable as 1/16" internal fittings. We recommend this style of union when connecting to an installed external nut.
Standard External/Internal Unions
| Tubing OD | Bore | Product No. |
|---|---|---|
| 1/32" | 0.25 mm | EZU.5 |
| 0.50 mm | EZU.5L | |
| 1/16" | 0.25 mm | EZU1C |
| 0.50 mm | EZU1M | |
| 0.75 mm | EZU1 | |
| 1/16" | EZU1T | |
| 1/8" | 1.00 mm | EZU2 |
| 2.0 mm | EZU2L | |
| 1/8" | EZU2T |
Bulkhead External/Internal Unions
The "Hole" heading in the table below refers to the size of the hole required for mounting the union through a bulkhead or panel.
| Tubing OD | Bore | Hole | Product No. |
|---|---|---|---|
| 1/16" | 0.25 mm | 5/16" | EZBU1C |
| 0.50 mm | 5/16" | EZBU1M | |
| 0.75 mm | 5/16" | EZBU1 | |
| 1/16" | 5/16" | EZBU1T | |
| 1/8" | 1.00 mm | 7/16" | EZBU2 |
| 2.0 mm | 7/16" | EZBU2L | |
| 1/8" | 7/16" | EZBU2T |

