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Four grey plastic cross-shaped tubing connectors on a plain background

Unique-Bargains

Unique-Bargains 4mm Cross Air Tubing Connector Grey 4 Pack

SKU CH-BHRK-CW48V

Connects four 4 mm air lines in a cross layout for aquarium or RC pneumatic systems

  • TypeToys - Remote & Radio Controlled
  • Cross design splits airflow four ways
  • 4 mm outlets fit standard 12 mm aquarium tubing
  • Grey plastic resists corrosion in wet environments
  • 42 × 37 × 12 mm body keeps installation compact
  • Pack of four covers multiple tank connections

Aquarium Cross Connector 4-Pack

This set provides four grey plastic connectors for standard 4 mm aquarium air tubing. The cross design splits a single line into three directions for simple air distribution. Each piece measures 42 by 37 by 12 mm and weighs 9 g. The pack suits hobbyists building or extending a pneumatic layout.

Replaces Single-Outlet Fittings

Swap basic straight or T-shaped fittings when a build needs three branches from one feed. The jump is worth it if the current layout forces multiple connectors in series, adding leak points. The 11 mm thread diameter matches common 12 mm airline tubing for a secure push fit.

Suits Multi-Tank Air Systems

Ideal for aquarists running several air stones or sponge filters from one pump. Not for buyers who need a straight-through joiner, a two-way T, or a valve to regulate flow. Also unsuitable for high-pressure pneumatic circuits beyond low-pressure aquarium use.

Highlights

  • Cross design splits airflow four ways
  • 4 mm outlets fit standard 12 mm aquarium tubing
  • Grey plastic resists corrosion in wet environments
  • 42 × 37 × 12 mm body keeps installation compact
  • Pack of four covers multiple tank connections

Specifications

BrandUnique Bargains
TypeToys - Remote & Radio Controlled

Questions about this item

What outer-diameter tubing fits the 4 mm outlets on these connectors?

The outlets accept 4 mm inner-diameter tubing; the supplier notes they are intended for 12 mm aquarium air line.

How do you attach the tubing to the 11 mm barbs without leaks?

Push the tubing fully over each barb until it seats against the body; the common mistake is stopping short of the flange.

When should the grey plastic connectors be replaced?

Replace them if the barbs crack, the cross body warps, or air leaks appear at the tubing joints after prolonged use.

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