Superlok 1/2" Union Cross SUC-8, 316 Stainless

Superlok and its distributors publish the Swagelok SS-810-4 as the cross reference for this part. Genuine Swagelok SS-810-4 was listed at $137.53 in October 2026. The nearest Superlok distributor price we could find was $47.99 on a one to two week lead. There are ten on the shelf in Bend.

What it is

• Four ports, all 1/2 inch tube OD, all two-ferrule compression. Not a reducing cross, and no NPT ends.
• 316 stainless body, with nuts and ferrules on all four ports
• The same make-up as the rest of the Superlok tube fitting family, so it goes together with the same wrench work as a plain union
• Straight through on both axes, so flow is not restricted more on one path than the other

Where it goes

• Instrument manifolds, where a gauge and a transducer both tap the same point on a line
• Four-way junctions on a skid, instead of stacking two tees and a nipple and adding two more leak paths
• Splitting a solvent or nitrogen header to two branches while keeping the run straight through
• Anywhere a relief path and a gauge have to come off the same point as the line itself

A cross is almost always the right answer over two tees in series. Fewer joints, shorter run, less holdup volume, and one fitting to leak check instead of two.

Specifications

Superlok publishes a dimension table for this part but does not define what its letters mean, so the center to end and overall figures are not reproduced here. We would rather leave a blank than put a drawing dimension on a web page and have somebody cut a tube to it. Call 541-330-6409 and we will measure the part in hand.

Ratings

3P Certz engineering report ECR-250902-R0 covers Superlok 316 stainless tube fittings up to 1 inch at 2400 psi (165 bar) and -320 F to 1200 F (-196 C to 649 C). That is the fitting family figure in the report. Superlok does not publish a working pressure for this part on its own, and what your line actually holds is set by your tubing wall and by the weakest component on the circuit, not by the fitting.

Fitment

• Fits 1/2 inch OD tube on all four ports. It does not fit 3/8 inch or 3/4 inch, and it is not a reducing cross.
• No NPT ports. If you need to pick up a threaded gauge or transducer, you need an adapter at that port.
• Not a tri-clamp part and not a hose fitting.
• Tube, and spare nut and ferrule sets, are separate items.
• If two ways is all you need, we stock the Swagelok SS-810-6 plain union in the same 1/2 inch size.
• If the line has to cross a panel, we stock the Superlok SBHU-8 bulkhead union.

$45.00, priced on this page rather than behind a quote form. Ten on the shelf. Ships from Bend, Oregon.