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Transparent plastic L-shaped inline valve connectors for 4mm tubing, pack of 30

Unique-Bargains

Unique-Bargains L-Shaped Non-Return Valve Tubing Connectors 4mm 30pcs

SKU CH-NNR3-WRPBJ

L-shaped non-return valves connect 4mm tubing in aquarium air lines, supplied in a pack of 30 transparent plastic pieces

  • 30 connectors included for multiple aquarium installations
  • L-shaped 21 mm body fits tight corners in plumbing
  • Non-return valve prevents backflow in air lines
  • Transparent plastic shows flow direction at a glance
  • Barbed 5 mm ends grip 4 mm tubing securely

L-Shaped Non-Return Valve Connectors

These 30-piece packs supply inline check valves for 4mm internal-diameter aquarium air lines. The transparent plastic bodies resist corrosion and are non-toxic for fish and plants. Each barb accepts 4mm or 5/32 inch tubing for a secure, leak-resistant fit.

Upgrade from straight barbs or missing check valves

Replace simple straight connectors that allow back-siphoning when pumps stop. The L-shaped body routes tubing neatly around tank corners while the internal flap prevents water from draining into the pump. The improvement is worthwhile whenever the air line runs below water level or spans a long distance.

Capacity and headroom for typical aquarium setups

Thirty valves cover multiple tanks, manifold branches or future maintenance spares. The 21mm by 21mm footprint fits inside standard hood channels and behind background panels. Flow restriction is minimal for common diaphragm pumps, but very high-output blowers may exceed the valve’s cracking pressure.

Highlights

  • 30 connectors included for multiple aquarium installations
  • L-shaped 21 mm body fits tight corners in plumbing
  • Non-return valve prevents backflow in air lines
  • Transparent plastic shows flow direction at a glance
  • Barbed 5 mm ends grip 4 mm tubing securely

Specifications

BrandUnique Bargains

Questions about this item

Will the 4 mm barbs fit standard aquarium airline tubing?

Yes, the connectors accept 4 mm or 5/32 inch inner-diameter tube, which is the common size for aquarium air lines.

How do I install the L-shaped non-return valves without leaks?

Wet both the barb and the tubing before pushing them together; the moisture lets the tube slide on fully and seal against the 5 mm barb.

When should I replace these plastic check valves?

Replace them if air flows backward through the valve, if the plastic becomes brittle, or if a barb cracks after repeated tube changes.

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