




SALE PROHIBITED TO PERSONS UNDER 18 - FREE SHIPPING FROM €40 (Mainland Spain only - Max. 25 Kg)
125 mm Non-Return Damper. designed to control the direction of flow in Indoor cultivation ventilation ducts and technical rooms. Automatic closing by springs, easy installation and compatibility with standard diameters. Effective barrier against air backflow, odors and pests.

In professional ventilation systems, the 125 mm Anti-Return Flap. acts as a one-way valve: it allows airflow when the extractor pushes in the correct direction and closes automatically when the flow stops or tries to reverse.
Made of aluminum, it provides lightness and strength, integrating effortlessly into Ø125 mm lines with flexible or rigid ducts. This accessory helps stabilize negative pressure, protects activated carbon filters, and minimizes the entry of dust or insects through the duct.
In cannabis cultivation accessories installations, where extractors, intractors, and branches coexist, an anti-return flap prevents outside air from re-entering the circuit and extraction from escaping through undesired lines.
The operation is completely automatic, with no power consumption, and allows immediate improvements in odor control, condensation, and overall efficiency.
For online purchases, Hydroponics Blanes offers specialized advice, discreet shipping, and a catalog designed to assemble and expand grow tents and rooms with expertise, within a Grow Shop in Spain recognized as a trusted Grow Shop with options in cheap indoor grow tents.
The 125 mm Anti-Return Flap. is key in Indoor cultivation because it prevents uncontrolled air exchanges. By keeping the circuit sealed, climate control works more precisely, the filter retains odors more effectively, and temperature and humidity fluctuations between cycles are noticeably reduced.
It is used to block return and allow circulation in only one direction. This favors a stable negative pressure, helps prevent pests and dust that could enter through the duct, and prevents air from flowing back to the extractor or diverting through the intractor when the equipment is off.
As an indoor cultivation accessory, this aluminum model stands out for its quick installation with clamps, compatibility with standard ducts, and operation by closing springs that require no adjustments. Perfect for tents, compact rooms, and lines that share an outlet with other spaces.
It is used in extraction and intake circuits for auxiliary LED lamps, drying areas, technical rooms, and medium-sized tents. Essential when several lines converge at the same outlet, or when you want to prevent the flow from returning to undesired areas after turning off the extractor.
1) Confirm network diameter: 125 mm.
2) Identify the flow direction arrow on the housing.
3) Insert the 125 mm Anti-Return Flap. between duct sections with the blades oriented toward expulsion.
4) Secure with metal clamps and seal joints with aluminum tape to improve tightness.
5) Turn on the extractor to check opening; when stopped, check automatic closure by spring.
6) Perform periodic checks to remove dust that could interfere with closing.
One-way flow direction, better circuit tightness, more effective odor control with filter, reduction of condensation during stops, prevention of pests through the duct, and quick installation compatible with standard networks. A small component that brings great improvement in environmental stability.
Available at Hydroponics Blanes, trusted Grow Shop with discreet shipping and technical support. Complete catalog of ventilation, extractors, filters, ducts, and cheap indoor grow tents within a Grow Shop in Spain with experience in cannabis cultivation accessories for efficient installations.
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Alternative presentation: the 125 mm Anti-Return Flap. ensures that air moves in only one direction, preventing unwanted re-entries and leaks. Lightweight and strong aluminum piece with automatic closing springs, ideal for tents and rooms where air efficiency and order make the difference. At Hydroponics Blanes you can find standard diameters, advice to choose compatibilities, discreet shipping, and everything needed to design and maintain Indoor cultivation.
Online Grow Shop Hydroponics Blanes. Everything needed for installation and maintenance of indoor crops is available with shipping throughout Spain in 24/48 h. SALE TO MINORS UNDER 18 YEARS OLD PROHIBITED. After each purchase, an email arrives with a 5% discount code for the next order.
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