--- product_id: 19968098 title: "42725 2 in. Backwater Valve Device for Integral Trap Shower Drain" brand: "oatey" price: "Β£10.86" currency: GBP in_stock: true reviews_count: 10 category: "Oatey" url: https://www.desertcart.co.uk/products/19968098-42725-2-in-backwater-valve-device-for-integral-trap-shower store_origin: GB region: United Kingdom --- # 3.75-inch deep sump bowl capacity One-piece trap drain & cleanout design 2-inch FIP threaded connection 42725 2 in. Backwater Valve Device for Integral Trap Shower Drain **Brand:** oatey **Price:** Β£10.86 **Availability:** βœ… In Stock ## Summary > 🚿 Stop backups before they start β€” the pro’s choice for flawless drainage! ## Quick Answers - **What is this?** 42725 2 in. Backwater Valve Device for Integral Trap Shower Drain by oatey - **How much does it cost?** Β£10.86 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/19968098-42725-2-in-backwater-valve-device-for-integral-trap-shower) ## Best For - oatey enthusiasts ## Why This Product - Trusted oatey brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **High-Capacity Sump Bowl:** Deep 3.75-inch sump bowl handles large water volumes effortlessly - β€’ **Seamless Sewage Defense:** Prevents costly backflow with integrated backwater valve technology - β€’ **Robust 2-Inch Threaded Fit:** Precision FIP threading ensures leak-proof, solvent weld installation - β€’ **Trusted Legacy Performance:** Backed by Oatey’s century-long reputation in professional plumbing - β€’ **Streamlined One-Piece Design:** Simplifies maintenance with combined trap drain and cleanout access ## Overview The Oatey 42725 2-inch Backwater Valve Device is a professional-grade integral trap shower drain that prevents sewage backup while allowing efficient drainage. Featuring a solvent weld 2-inch FIP threaded connection, a deep 3.75-inch sump bowl for high capacity, and a one-piece trap drain/cleanout design, it offers reliable, easy installation and maintenance. Trusted by plumbing pros for over 100 years, this device is engineered to protect your home from costly water damage with proven durability and performance. ## Description Product Description Oatey Integral Floor Drain with P-Trap is available with an optional backwater device that transforms the drain into a backwater valve, allowing drainage while preventing sewage backup. Oatey products have earned the trust of plumbing professionals for over 100 years. From the Manufacturer Oatey products can be found in residential and commercial applications and have achieved excellent brand name recognition with consumers. All products are backed with the highest quality technical and customer support programs in the industry Review: Works well if you don't screw it up like I did - Fits my 1940's basement floor drain "P-Trap drain" just perfectly. Finally got the old one out and this dropped in like a charm. Be aware the rubber rim is thin and not robust material. The seal, when I originally installed it, was very good. However... I tried to lube it up with WD40 after it was installed, thinking that might tighten the seal, since it did upleak a tiny bit when my washing machine is trying to force-feed a tub-full of water down the basement drain (only enough to very slightly fill the drain's cup). However the WD40 corrupted the rubber, causing it to buckle & crinkle and therefore it started leaking way too much. I then tried Dupont Silicone spray, which is supposed to be safe on rubber. I guess it was the volatiles used in the spray delivery, because it buckled again and I had to replace it with a fresh one. Which, thanks to the low price of this item, is not painful. It would be nicer if this had a nice big faux-rubber "O" ring that could withstand some crap instead of a thin, obviously real-rubber skirt, but as long as I don't do anything stupid, I think the seal this provides is solid enough, and will hopefully last a while. Make sure to pair it with a water-leak alarm just in case ;) P.S. Yes my antique cast-iron 1939 version of this ball valve was difficult to get out... it was rusted in there good. Finally the light bulb came on, and I grabbed my sawz-all with a metal-cutting blade and cut a little chunk out of the old collar, after that I was able to chisel it loose and unscrew it. Just don't go deeper than necessary with the sawz-all to avoid damaging the threads in the female portion of the drain in the floor. Hope that helps -- it only took me 14 years to figure out how to get the old one out!! :) Review: Really Simple Back Flow Preventer - Easy peasy. You put it in your floor drain, it stops back flows during storm surges etc. Hasn't been through a big storm yet but looks like it should work in theory. ## Features - Trap drain allows for drainage while preventing sewage backup - Solvent weld over 2 in. Scheudle 40 DWV pipe - One piece trap drain/cleanout design - 3-3/4 in. deep sump bowl for large capacity - Built in 2 in. FIP threadway for backwater device ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B000BQWR1I | | Best Sellers Rank | #389,033 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #636 in Bathroom Sink Drains #1,765 in Showers & Shower Parts | | Brand Name | Oatey | | Connector Type | connector_type | | Customer Reviews | 4.5 4.5 out of 5 stars (79) | | Exterior Finish | exterior_finish | | Global Trade Identification Number | 00038753427256 | | Included Components | Backwater Valve | | Inlet Connection Size | 2 Inches | | Inlet Connection Type | threaded | | Item Dimensions | 2 x 2 x 2.25 inches | | Item Type Name | Backwater Valve Device | | Item Weight | 22.68 g | | Manufacturer | Oatey | | Manufacturer Warranty Description | 1-year limited | | Material Type | PVC | | Model Number | 42725 | | Number of Pieces | 1 | | Number of Ports | 2 | | Outlet Connection Size | 2 Inches | | Outlet Connection Type | FIP | | Size | 2 Inch | | Specification Met | ASTM | | Thread Size | 2 inches | | Thread Type | FIP | | UPC | 038753427256 | | Unit Count | 1.0 Count | | Valve Type | Backwater Valve | ## Product Details - **Brand:** Oatey - **Exterior Finish:** exterior_finish - **Inlet Connection Size:** 2 Inches - **Inlet Connection Type:** threaded - **Item dimensions L x W x H:** 2 x 2 x 2.25 inches - **Material:** PVC - **Number of Ports:** 2 - **Outlet Connection Size:** 2 Inches - **Outlet Connection Type:** FIP - **Specification Met:** ASTM ## Images ![42725 2 in. Backwater Valve Device for Integral Trap Shower Drain - Image 1](https://m.media-amazon.com/images/I/71AzfxTjSFL.jpg) ## Questions & Answers **Q: Is this a drain trap(pictured) or just a backwater valve?** A: It is a trap with the option of having a ball check valve to prevent backwater. **Q: Does the backwater device come with it?** A: no you have to purchase it separately. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Works well if you don't screw it up like I did *by R***N on June 9, 2018* Fits my 1940's basement floor drain "P-Trap drain" just perfectly. Finally got the old one out and this dropped in like a charm. Be aware the rubber rim is thin and not robust material. The seal, when I originally installed it, was very good. However... I tried to lube it up with WD40 after it was installed, thinking that might tighten the seal, since it did upleak a tiny bit when my washing machine is trying to force-feed a tub-full of water down the basement drain (only enough to very slightly fill the drain's cup). However the WD40 corrupted the rubber, causing it to buckle & crinkle and therefore it started leaking way too much. I then tried Dupont Silicone spray, which is supposed to be safe on rubber. I guess it was the volatiles used in the spray delivery, because it buckled again and I had to replace it with a fresh one. Which, thanks to the low price of this item, is not painful. It would be nicer if this had a nice big faux-rubber "O" ring that could withstand some crap instead of a thin, obviously real-rubber skirt, but as long as I don't do anything stupid, I think the seal this provides is solid enough, and will hopefully last a while. Make sure to pair it with a water-leak alarm just in case ;) P.S. Yes my antique cast-iron 1939 version of this ball valve was difficult to get out... it was rusted in there good. Finally the light bulb came on, and I grabbed my sawz-all with a metal-cutting blade and cut a little chunk out of the old collar, after that I was able to chisel it loose and unscrew it. Just don't go deeper than necessary with the sawz-all to avoid damaging the threads in the female portion of the drain in the floor. Hope that helps -- it only took me 14 years to figure out how to get the old one out!! :) ### ⭐⭐⭐⭐⭐ Really Simple Back Flow Preventer *by K***Z on June 11, 2025* Easy peasy. You put it in your floor drain, it stops back flows during storm surges etc. Hasn't been through a big storm yet but looks like it should work in theory. ### ⭐⭐⭐ 3rd time order - rubber skirt decays at 3 years. *by D***O on November 8, 2024* These work in our home basement floor drains. However, the rubber skirt shows buckling and failure to seal, at about the 3 year mark. Be prepared to replace these every 3 years :(. ## Frequently Bought Together - Oatey 42725 Backwater Valve Device, 2", White - Minimprover Internal Backwater Valve,2-F 2" Float Model Flood-Guard for 2-inch Flood Drains,Drain Backflow Preventer for Sewer Flood Protection - General Specialties Flood-Guard for 2" Flood Drains --- ## 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/19968098-42725-2-in-backwater-valve-device-for-integral-trap-shower](https://www.desertcart.co.uk/products/19968098-42725-2-in-backwater-valve-device-for-integral-trap-shower) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-23*