--- product_id: 152832628 title: "Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White" brand: "mkk" price: "Β£11.01" currency: GBP in_stock: true reviews_count: 13 category: "Mkk" url: https://www.desertcart.co.uk/products/152832628-connector-with-backflow-flap-check-valve-connector-ventilation-pipe-round store_origin: GB region: United Kingdom --- # Durable white PVC plastic 100 mm diameter fit Backflow flap prevents air return Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White **Brand:** mkk **Price:** Β£11.01 **Availability:** βœ… In Stock ## Summary > πŸŒ€ Keep your air fresh and your space flawless with the ultimate backflow barrier! ## Quick Answers - **What is this?** Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White by mkk - **How much does it cost?** Β£11.01 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/152832628-connector-with-backflow-flap-check-valve-connector-ventilation-pipe-round) ## Best For - mkk enthusiasts ## Why This Product - Trusted mkk brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Sleek & Durable PVC Build:** Smooth white finish blends with any ventilation setup while resisting wear and tear. - β€’ **One-Way Airflow Protection:** Backflow flap ensures fresh air stays in, blocking unwanted drafts and odors. - β€’ **Seamless 100 mm Connection:** Perfectly fits standard 4-inch ventilation pipes for hassle-free installation. - β€’ **Versatile Indoor/Outdoor Use:** Engineered for apartments, homes, and commercial spacesβ€”wherever clean airflow matters. - β€’ **Trusted Quality with Warranty:** Backed by a 2-year manufacturer guarantee for peace of mind and lasting performance. ## Overview This 100 mm diameter PVC connector with an integrated backflow flap is designed for ventilation systems in residential and commercial buildings. It prevents air from flowing backward, ensuring only fresh air circulates. The white, smooth plastic finish offers durability and aesthetic appeal, fitting standard 4-inch ducts seamlessly. Ideal for maintaining clean airflow, it comes with a 2-year manufacturer warranty for reliable, long-term use. ## Description Ventilation systems are intended for air distribution in ventilation systems of apartments, houses and commercial buildings. Perfect for places where the air should not return and only fresh air should remain. Connection from pipe to pipe. Specifications: Material: PVC plastic; Colour: white; Diameter: 100 mm. Note: The backflow flap may be red, blue or green in contrast to the product image. The connector itself is white Review: Fits 4" fine - Fit a 4" bath vent with no issues Review: Good. - No gaskets or o-rings to help seal, but should stop most back draft. Here is a much better one: AC Infinity 4" Backdraft Damper, One-Way Airflow Ducting Insert with Spring-Loaded Folding Blades for 4” Ducting in Range Hoods and Bathrooms Fans https://a.co/d/hodpLQl I used this one in a corner just above the room and the better one at the outside wall. Fits nicely into a 4" 90. ## Features - Material: PVC plastic - Colour: white - Diameter: 100 mm - Kitchen - Volume: 0.001 m3 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00FCE0RSE | | Assembled Diameter | 1 Centimeters | | Batteries Included? | No | | Batteries Required? | No | | Best Sellers Rank | #445,000 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #1,202 in HVAC Ducting | | Brand | MKK | | Color | White | | Connector Type | Plug | | Customer Reviews | 4.3 4.3 out of 5 stars (3,470) | | Cutting Diameter | 1 Centimeters | | Date First Available | January 27, 2021 | | Exterior Finish | Smooth plastic surface | | Included Components | No | | Is Discontinued By Manufacturer | No | | Item Package Quantity | 1 | | Item Weight | 1.76 ounces | | Item model number | KO100-22 | | Manufacturer | MKK | | Material | Polyvinyl Chloride | | Number of Pieces | 1 | | Part Number | A289a_SML | | Shape | round | | Size | Klein | | Thread Size | 4 inch | | Thread Type | UN | | Usage | Inside, Outside | | Warranty Description | 2 Year Manufacturer Guarantee. | ## Product Details - **Brand:** MKK - **Color:** White - **Connector Type:** Plug - **Exterior Finish:** Smooth plastic surface - **Item dimensions L x W x H:** 3.94 x 3.94 x 2.36 inches - **Material:** Polyvinyl Chloride - **Number of Pieces:** 1 - **Size:** Klein - **Thread Size:** 4 inch - **Thread Type:** UN ## Images ![Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - Image 1](https://m.media-amazon.com/images/I/410JRbLJ-6L.jpg) ![Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - Image 2](https://m.media-amazon.com/images/I/61Sf3d3RwsL.jpg) ![Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - Image 3](https://m.media-amazon.com/images/I/41NTOGieKAL.jpg) ![Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - Image 4](https://m.media-amazon.com/images/I/41UqnXvbw6L.jpg) ![Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - Image 5](https://m.media-amazon.com/images/I/4161WRlGmgL.jpg) ## Available Options This product comes in different **Color, Size** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Fits 4" fine *by P***R on November 14, 2025* Fit a 4" bath vent with no issues ### ⭐⭐⭐⭐ Good. *by G***W on August 7, 2024* No gaskets or o-rings to help seal, but should stop most back draft. Here is a much better one: AC Infinity 4" Backdraft Damper, One-Way Airflow Ducting Insert with Spring-Loaded Folding Blades for 4” Ducting in Range Hoods and Bathrooms Fans https://a.co/d/hodpLQl I used this one in a corner just above the room and the better one at the outside wall. Fits nicely into a 4" 90. ### ⭐⭐⭐⭐⭐ Works as Expected *by C***P on December 7, 2020* Nice damper for 4 inch metal ducting, used it to isolate the existing dryer exhaust duct, from an ad hoc fan driven exhaust to vent my cat’s sealed litter box cabinet. Must install vertically. The existing dryer flow creates outward suction which seals the damper so there is no backdraft towards the newly installed fan exhaust ( very necessary to minimize lint to build up). When the fan is in operation ( with or without the counter dryer suction) the damper opens up and allows the stink to vacate my basement.. just what I needed...( the damper is installed between the t-shaped duct and the flexible piping in the picture) ## Frequently Bought Together - Connector with Backflow Flap, Check Valve, Connector, Ventilation Pipe, Round Duct, Ventilation System, Pipe Connector, Diameter 100 mm, White - EesTeck 4" (Diameter) Adjustable 304 Stainless Steel Duct Clamps Hose Clamp Pipe Clamp Air Ducting Clamp worm drive hose clamps (4Pcs, 91mm-114mm) - AC Infinity Flexible 4-Inch Aluminum Ducting, Heavy-Duty Four-Layer Protection, 25-Feet Long for Heating Cooling Ventilation and Exhaust --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/152832628-connector-with-backflow-flap-check-valve-connector-ventilation-pipe-round](https://www.desertcart.co.uk/products/152832628-connector-with-backflow-flap-check-valve-connector-ventilation-pipe-round) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-21*