--- product_id: 55288887 title: "MF3 Rat Barrier- Non Return Valve (DRAINS) 4\" Clay or Plastic pipe" brand: "multi-flap" price: "VT19325" currency: VUV in_stock: true reviews_count: 8 category: "Multi Flap" url: https://www.desertcart.vu/products/55288887-mf3-rat-barrier-non-return-valve-drains-4-clay-plastic store_origin: VU region: Vanuatu --- # Reduces backflow effectively Stops rodent & snake entry Easy DIY fit, no plumber needed MF3 Rat Barrier- Non Return Valve (DRAINS) 4" Clay or Plastic pipe **Brand:** multi-flap **Price:** VT19325 **Availability:** ✅ In Stock ## Summary > 🚪 Shut the door on pests—secure your drains with ease! ## Quick Answers - **What is this?** MF3 Rat Barrier- Non Return Valve (DRAINS) 4" Clay or Plastic pipe by multi-flap - **How much does it cost?** VT19325 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.vu](https://www.desertcart.vu/products/55288887-mf3-rat-barrier-non-return-valve-drains-4-clay-plastic) ## Best For - multi-flap enthusiasts ## Why This Product - Trusted multi-flap brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Backflow Barrier:** Innovative gasket and spring mechanism ensure reliable backflow prevention, keeping your drains clean and odor-free. - • **Light & Pest Shield:** Blocks light penetration that attracts pests, creating an invisible fortress against unwanted intruders. - • **Ultimate Pest Blockade:** Seals off drains to prevent rodents and snakes from invading your home, maintaining a hygienic environment. - • **DIY Installation Mastery:** Fits all 4" (110mm) clay, plastic & cast pipes—no plumber required, saving you time and money. - • **One Valve, Multiple Toilets:** A single valve protects multiple toilets by closing the discharge pipe instantly after use. ## Overview The MF3 Rat Barrier Non-Return Valve is a high-grade plastic, 4-inch lift check valve designed for easy, no-plumber installation on clay, plastic, or cast drain pipes. It prevents rodent and snake ingress by sealing the drain outlet immediately after wastewater passes, while also reducing backflow and blocking light that attracts pests. Ideal for protecting multiple toilets with a single valve, it offers a cost-effective, durable solution to keep your drainage system pest-free. ## Description The MF3 Multiflap is to be used for 4" - 110mm Plasticor Salt Glazed - Clay Underground pipework. PLEASE NOTE: The MF3 MultiFlap is NOT suitable for an outlet pipe into the manhole, it is only be suitable for the pipe that exits manhole to the sewer, therefore you need to locate the last chamber before sewer. How does it work? The Multi-Flap MF3 fits into the channel exit in an inspection chamber to stop back flow or rats entering your drainage system. The Multi-Flap is a one-way non-return valve that fits easily to the exit pipe from your house to the street sewer. This means waste still goes out from your house, but immediately after the waste water has gone, the flap closes to prevent anything nasty coming up the wrong way. The prevention method and the ease with which the Multi-Flap can be installed makes these products truly unique. How can vermin get into my drains? Since the 1950's drainage systems have been much less isolated from the main street sewer and this has allowed rats more access into peoples drainage systems. Damaged or unmaintained storm drains and sewer pipes easily allow vermin access into the main drainage systems. From here they can enter your home by travelling through sewers, up pipes and exiting from the foul air outlet at roof level or swimming through the water contained in your toilet system. The MultiFlap ensures you're protected by keeping them in the sewers where the authorities can deal with them. Brilliant new device to stop rats gaining access into your drainage system. PLEASE NOTE: The MF3 MultiFlap is made of a high grade plastic, but a determined rat can, and will, chew through plastic. Although this is very rare, it is possible. If this this concerns you, you might like to consider the more expensive stainless steel flap non return valves. Review: Great value product. - Bought these a couple of years ago. Easy to fit and no problems with them at all. A lot less expensive than metal ones and seem to last. Review: The door is sprung with just the right amount of tension to close tight once waste or water has passed through - For ease of fitting it's a 5 star product, once I had chipped away a small section of benching in the sewer it slotted in and worked perfectly. The door is sprung with just the right amount of tension to close tight once waste or water has passed through, which it does without issue. Time will tell if the filthy, horrible things are getting in via the drains but already activity seems to of dropped off meaning there may just be the odd one that needs to leave and shut the door on the way out. Providing the door spring is stainless steel and they don't chew through the plastic/polyprop door itself it appears well made and should last. ## Features - Easy to fit - no need for a plumber - Will fit into all 4 inch (110mm) drain pipes, clay, plastic and cast, Fits directly onto the drain outlet - No need to remove your toilet - Stops light penetration that attracts rodents and snakes - Only one valve needed for multiple toilets - Provides a closed door to pests in the discharge pipe under closed conditions - Will not fall down the pipe due to a gasket which opens the rubber - Reduces backflow - Important: Please print installation instructions before fitting ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00PLN1UPA | | Best Sellers Rank | 52,701 in Garden ( See Top 100 in Garden ) 5,294 in Pest Control Products | | Brand | Multi-Flap | | Connector Type | Sweat, Socket Weld | | Country of Origin | United Kingdom | | Customer Reviews | 3.6 3.6 out of 5 stars (107) | | Exterior Finish | Plastic | | Inlet Connection Size | 4 Inches | | Inlet Connection Type | Socket Weld | | Manufacturer | Multi-Flap | | Material | Plastic | | Model Number | MF3 | | Number of Ports | 1 | | Outlet Connection Size | 4 Inches | | Outlet Connection Type | Sweat | | Size | 4 inches | | Thread Size | 4 inches | | Thread Type | Non-threaded | | UPC | 609788764618 | | Unit Count | 1.0 count | | Valve Type | Lift Check Valve | ## Product Details - **Brand:** Multi-Flap - **Exterior finish:** Plastic - **Inlet connection size:** 4 Inches - **Inlet connection type:** Socket Weld - **Manufacturer:** Multi-Flap - **Material:** Plastic - **Number of ports:** 1 - **Outlet connection size:** 4 Inches - **Outlet connection type:** Sweat - **UPC:** 609788764618 ## Images ![MF3 Rat Barrier- Non Return Valve (DRAINS) 4" Clay or Plastic pipe - Image 1](https://m.media-amazon.com/images/I/31QHytiNs2L.jpg) ## Questions & Answers **Q: Does it also stop odours ?** A: Sounds like you installed it the wrong way round, as the pressure to dislodge it, should have poured thru the gate, not against the gate **Q: Is there a possibility that the flap can stick/stay open over time (i,e. Spring/hinge failure)?** A: There are always possibilities with these things but after selling them for past 8 years we have not had it happen... **Q: is the valve open easily when flushing, would spring reduce the flushing flow or cause any blocking or partial blocking?** A: I have 2 fitted in my main drain and have not experienced any blockage problemsThe flap lifts when water goes through on light water flow also opens up when a toilet is flushed allowing paper and other particles to flow throughBoth valves have been fitted now for 5months **Q: Hi, my clay sewer coming out of my kitchen has a diameter of about 95mm. Does this product would work with this kind of sewer? Thanks** A: Yes it should work for you, check your measurements as it is designed to fit a 4'' or 100mm pipe. Ensure that the trap sits square in the drain and you tack it down with silicone. Test that the door swings open. Better to clean out the area before you start. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great value product. *by B***K on 12 June 2020* Bought these a couple of years ago. Easy to fit and no problems with them at all. A lot less expensive than metal ones and seem to last. ### ⭐⭐⭐⭐ The door is sprung with just the right amount of tension to close tight once waste or water has passed through *by D***N on 2 February 2016* For ease of fitting it's a 5 star product, once I had chipped away a small section of benching in the sewer it slotted in and worked perfectly. The door is sprung with just the right amount of tension to close tight once waste or water has passed through, which it does without issue. Time will tell if the filthy, horrible things are getting in via the drains but already activity seems to of dropped off meaning there may just be the odd one that needs to leave and shut the door on the way out. Providing the door spring is stainless steel and they don't chew through the plastic/polyprop door itself it appears well made and should last. ### ⭐ Broke whilst being fitted! So useless and a waste of money for a bit of plastic!!!! *by P***M on 12 July 2023* My husband attempted to fit following the instructions but the flap broke whilst he was putting the valve into the pipe. Totally useless and clearly was either faulty or just not fit for purpose. To top it all, I cannot return the item as it has been down the sewer!!! I am very unhappy about wasting £25 on a piece of plastic that has not served its purpose and am certainly not wasting another £25. ## Frequently Bought Together - Multi-Flap MF3 Rat Barrier- Non Return Valve (DRAINS) 4" Clay or Plastic pipe - Roshield Rat Drain Guard | Stop Rats within Drainage & Properties | Rodent Flap Control & Prevention Proofing (Stainless Steel 4"/110mm) - Retro Fit 110mm 4 inch Drain Non Return Valve with Stainless Steel Flap --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.vu/products/55288887-mf3-rat-barrier-non-return-valve-drains-4-clay-plastic](https://www.desertcart.vu/products/55288887-mf3-rat-barrier-non-return-valve-drains-4-clay-plastic) --- *Product available on Desertcart Vanuatu* *Store origin: VU* *Last updated: 2026-04-22*