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Black G1/4 bulkhead coupling with 21mm mounting hole

Alphacool

Alphacool 65166 G1/4 Bulkhead Coupling Black 21mm

SKU CH-3PGJ-4QEWN MPN 65166

G1/4 bulkhead connector passes tubing through a 21 mm panel cut-out for custom liquid-cooling loops

  • FeaturesThis bulkhead connector is perfect for applications such as
  • Secure panel pass-through with G1/4 threads
  • High-flow interior for unrestricted coolant movement
  • Deep Black chromatised finish resists peeling
  • 21 mm mounting hole fits standard cut-outs
  • Brass body with bonded surface for lasting colour

G1/4 Bulkhead Connector for Enclosures

This Alphacool bulkhead coupling provides a G1/4 pass-through for routing tubing through a panel or enclosure wall. It suits custom liquid-cooling builders who need a clean external connection point. The 21 mm mounting hole size matches standard panel cut-outs for this thread type. The Deep Black finish resists peeling thanks to a chromatised surface bonded to the brass body.

Installation Notes and Common Issues

The connector threads into a 21 mm hole and is secured with the supplied lock nut, so only basic hand tools are required. Leaks usually come from an uneven panel surface or an overtightened nut that distorts the O-ring seal. Alignment of the two attached fittings must be checked before final tightening to avoid stress on the tubing runs. The part ships as a single connector without additional fittings.

G1/4 Thread Limits and Flow

The G1/4 thread limits compatibility to components sharing that same thread standard. Inner diameter is optimised for high flow, but maximum flow rate still depends on the tubing and fittings chosen for either side. The connector adds a fixed length to the loop, so available panel depth must accommodate it. No other thread adapters or sealing methods are included.

Highlights

  • Secure panel pass-through with G1/4 threads
  • High-flow interior for unrestricted coolant movement
  • Deep Black chromatised finish resists peeling
  • 21 mm mounting hole fits standard cut-outs
  • Brass body with bonded surface for lasting colour

Specifications

BrandAlphacool
Model65166
FeaturesThis bulkhead connector is perfect for applications such as looping through of tubing through the back or side of an enclosure with the help of two fittings. The bulkhead connector itself is safely fixated with the counter-nut and the 1/4“ inner threads can then be used to connect two fittings of your choice.
Part Number65166

Questions about this item

How can I confirm the 21 mm bulkhead coupling is seated correctly after installation?

Verify the connector sits flush against the panel with the G1/4 threads fully engaged on both sides and no visible gap around the 21 mm mounting hole.

What comes in the box and which additional fittings must I purchase separately?

The package includes one Alphacool G1/4 bulkhead connector in Deep Black; you will need two standard G1/4 fittings to attach your tubing.

Which colour variant should I choose for a black-themed loop?

Select the Deep Black version to match a black colour scheme.

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