--- title: "EPDM Rubber Well Nuts" description: "EPDM Rubber Well Nuts to Trade series (rubber blind nuts): sizes M3 to M8, dia 8-16 mm. 5 catalogued sizes with materials and finishes." url: https://engineeringhardware.com/fastener/epdm-rubber-well-nuts/ source: Engineering Hardware & Fasteners --- # EPDM Rubber Well Nuts Nuts · EPDM Rubber Well Nuts 5 catalogued sizes, dimensioned to Trade series (rubber blind nuts). Pick any row and the technical drawing redraws to it. EPDM Rubber Well Nuts to Trade series (rubber blind nuts) are catalogued in sizes M3 to M8, with dia 8-16 mm. 5 sizes are held in the table below, and the technical drawing redraws to whichever row you select. - **Standard:** Trade series (rubber blind nuts) - **Size range:** M3-M8 - **Dia:** 8-16 mm - **Catalogued sizes:** 5 Dimensions are nominal values from the governing standard. Confirm the tolerance class for your application before ordering. ![EPDM Rubber Well Nuts technical product image](https://engineeringhardware.com/wp-content/uploads/2026/09/EPDM-Rubber-Well-Nuts-Rubber-Blind-Nuts.webp) Product catalog ## Related EPDM Rubber Well Nuts products [![Wholesale Nickel Plated Straight Through Injection Molded Copper Embedded Nut](https://img.engineeringhardware.com/Wholesale-Nickel-Plated-Straight-Through-Injection-Molded-Copper-Embedded-Nut.webp)](https://engineeringhardware.com/product/wholesale-nickel-plated-straight-through-injection-molded-copper-embedded-nut/) Hex & Other Standard Nuts ### [Wholesale Nickel Plated Straight Through Injection Molded Copper Embedded Nut](https://engineeringhardware.com/product/wholesale-nickel-plated-straight-through-injection-molded-copper-embedded-nut/) Round Head · DIN, ANSI, GB, JIS **US$0.0972 – 0.19**MOQ 5,000 pieces [![Heavy Duty Water Stop Nut for Basement Wall Casting](https://img.engineeringhardware.com/Heavy-Duty-Water-Stop-Nut-for-Basement-Wall-Casting.webp)](https://engineeringhardware.com/product/heavy-duty-water-stop-nut-for-basement-wall-casting/) Hex & Other Standard Nuts ### [Heavy Duty Water Stop Nut for Basement Wall Casting](https://engineeringhardware.com/product/heavy-duty-water-stop-nut-for-basement-wall-casting/) Wall Formwork · Steel **US$0.65**MOQ 50 pieces [![Yph Stainless Steel Hex Thin Nut](https://img.engineeringhardware.com/Yph-Stainless-Steel-Hex-Thin-Nut.webp)](https://engineeringhardware.com/product/yph-stainless-steel-hex-thin-nut/) Hex & Other Standard Nuts ### [Yph Stainless Steel Hex Thin Nut](https://engineeringhardware.com/product/yph-stainless-steel-hex-thin-nut/) Round Head · DIN, ANSI, GB, JIS, GOST, BSW, All **US$0.0084 – 0.0096**MOQ 1,000 pieces [![Malaxy Titanium Alloy Flange Hex Nut M5/M6/M8/M10 Bicycle High Strength Anodized Finish Class 10](https://img.engineeringhardware.com/Malaxy-Titanium-Alloy-Flange-Hex-Nut-M5-M6-M8-M10-Bicycle-High-Strength-Anodized-Finish-Class-10.webp)](https://engineeringhardware.com/product/malaxy-titanium-alloy-flange-hex-nut-m5-m6-m8-m10-bicycle-high-strength-anodized/) Hex & Other Standard Nuts ### [Malaxy Titanium Alloy Flange Hex Nut M5/M6/M8/M10 Bicycle High Strength Anodized Finish Class 10](https://engineeringhardware.com/product/malaxy-titanium-alloy-flange-hex-nut-m5-m6-m8-m10-bicycle-high-strength-anodized/) Allen Head · DIN, GB, ANSI, BSW, JIS, GOST **US$0.84 – 2.16**MOQ 10 pieces [![Custom Machining of Metal Shaped Stamped Nuts Stamping Parts](https://img.engineeringhardware.com/Custom-Machining-of-Metal-Shaped-Stamped-Nuts-Stamping-Parts.webp)](https://engineeringhardware.com/product/custom-machining-of-metal-shaped-stamped-nuts-stamping-parts/) Hex & Other Standard Nuts ### [Custom Machining of Metal Shaped Stamped Nuts Stamping Parts](https://engineeringhardware.com/product/custom-machining-of-metal-shaped-stamped-nuts-stamping-parts/) Hexagon Head · DIN, ANSI **US$0.024 – 0.12**MOQ 1,000 pieces [![Precision Machined Internal External Thread Nut OEM Supplier for Global Market](https://img.engineeringhardware.com/Precision-Machined-Internal-External-Thread-Nut-OEM-Supplier-for-Global-Market.webp)](https://engineeringhardware.com/product/precision-machined-internal-external-thread-nut-oem-supplier-for-global-market/) Hex & Other Standard Nuts ### [Precision Machined Internal External Thread Nut OEM Supplier for Global Market](https://engineeringhardware.com/product/precision-machined-internal-external-thread-nut-oem-supplier-for-global-market/) Hexagon Head · DIN, GB **US$0.012 – 12.00**MOQ 5,000 pieces [View all Hex & Other Standard Nuts →](https://engineeringhardware.com/fastener-products/nuts/hex-other-standard-nuts/) [Full product catalog](https://engineeringhardware.com/products/) ## Applications & Industries Where EPDM Rubber Well Nuts are used, and what decides the specification in each case. Stocked from M3 to M8. ### Industries that specify EPDM Rubber Well Nuts - **Vehicle body panels:** Rubber well nuts isolate and seal trim fasteners through thin skins. - **Motorcycle service:** Blind rubber inserts provide a thread where the rear face is inaccessible. - **Outdoor enclosures:** EPDM accommodates panel movement and keeps a small hole sealed. - **Equipment covers:** Stainless inserts resist corrosion while the rubber body clamps the panel. - **Maintenance & MRO:** Replacements matched to the existing bolt class, thread and finish. - **Building services:** Threaded rod, channel and suspension assemblies. ### Typical applications - adding a blind threaded point to a thin panel - matching hole diameter and grip range to the EPDM body - tightening only to the representative torque for the size - using the rubber body for isolation and sealing - completing a bolted joint on a stud, rod or bolt - locking an adjustment so it cannot drift ### Service conditions to specify against - **Marine and coastal:** Available in A4 (316) stainless for chloride exposure — coastal structures, pool halls, water treatment and deck hardware, where A2 will eventually pit. - **High load:** Supplied in ISO 898-1 property classes, so the joint can be designed to a stated proof load and tightened to a calculated torque rather than by feel. - **Sealed joints:** Used where the fixing has to keep water or air out as well as hold — the elastomer, not the fastener, decides service life. - **Match the class:** A nut below the bolt property class strips before the bolt reaches its own limit — pair class 8 nuts with 8.8 bolts, class 10 with 10.9. ### Where to use something else - Do not over-tighten a well nut; excess compression can pull the insert through the panel or damage the seal. [Full application guide: where EPDM Rubber Well Nuts are used, how to specify them, and the cases they are wrong for](https://engineeringhardware.com/applications/epdm-rubber-well-nuts/) ## Technical Drawing Dimensioned line drawing of M3 EPDM Rubber Well Nuts to Trade series (rubber blind nuts). Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected. - **Representative hole diameter (mm):** 8.0 - **Representative grip range (mm):** 0.4~4.0 - **Temperature range (u00b0C):** -30~+80 - **Representative tightening torque (Nu00b7m):** 0.5 - **Body / insert:** EPDM rubber / stainless threaded insert ## Dimensions & Specifications (Trade series (rubber blind nuts)) Every row below is a starting point for the customizer above — pick any size and the drawing will redraw to that row. | Thread size | Representative hole diameter (mm) | Representative grip range (mm) | Temperature range (u00b0C) | Representative tightening torque (Nu00b7m) | Body / insert | | --- | --- | --- | --- | --- | --- | | [M3](https://engineeringhardware.com/guide/size/m3-epdm-rubber-well-nuts/) | 8.0 | 0.4~4.0 | -30~+80 | 0.5 | EPDM rubber / stainless threaded insert | | [M4](https://engineeringhardware.com/guide/size/m4-epdm-rubber-well-nuts/) | 8.0 | 0.4~4.0 | -30~+80 | 0.4 | EPDM rubber / stainless threaded insert | | [M5](https://engineeringhardware.com/guide/size/m5-epdm-rubber-well-nuts/) | 9.7 | 0.4~4.9 | -30~+80 | 0.6 | EPDM rubber / stainless threaded insert | | [M6](https://engineeringhardware.com/guide/size/m6-epdm-rubber-well-nuts/) | 12.8 | 0.4~4.0 or 0.8~4.7 | -30~+80 | 1.0 | EPDM rubber / stainless threaded insert | | [M8](https://engineeringhardware.com/guide/size/m8-epdm-rubber-well-nuts/) | 16.0 | 0.4~4.0 | -30~+80 | 1.5 | EPDM rubber / stainless threaded insert | EPDM Rubber Well Nuts conform to Trade series (rubber blind nuts). As nuts, they are specified by the dimensions in the table below; this page also covers materials, finishes and typical uses. ## What Are EPDM Rubber Well Nuts? EPDM Rubber Well Nuts are nuts defined by Trade series (rubber blind nuts). They are selected by thread size and the dimensional characteristics shown below, and are available in a range of materials and finishes to suit the application and environment. ## Materials & Finishes Common materials include carbon steel (typically zinc plated or hot-dip galvanized), alloy steel in property classes 8.8, 10.9 and 12.9, and stainless steel A2 (304) or A4 (316) for corrosion resistance. Specify the material, property class and surface finish appropriate to your load and environment. ## Pricing EPDM Rubber Well Nuts are supplied to order. Pricing starts from approximately US$0.090 per piece for standard sizes in carbon steel; final pricing depends on size, material, finish and order quantity (MOQ applies). Submit your exact configuration with the quote form above. Custom manufacturing · Made to drawing ## Need a EPDM rubber well nuts outside the standard range? Height and across-flats are the two most often changed — a thinner nut for clearance, a larger hex for a tool that is already on the line. Made by cold heading or tapping. Minimum order from 2,000 pieces; samples within 7 days of drawing approval. [Custom nut manufacturing](https://engineeringhardware.com/custom/nuts/)[Send a drawing](https://engineeringhardware.com/custom/nuts/#rfq) Inside the plant ## Manufactured in our own plant This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided. 1. ![Wire rod feeding into a cold heading machine](https://engineeringhardware.com/wp-content/uploads/2026/08/09-wire-rod-feed-cold-heading-machine.webp) 01 **Cold heading** Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail. Head dimensions and under-head radius checked at set-up and per shift. 2. ![Thread rolling machine producing bolt threads](https://engineeringhardware.com/wp-content/uploads/2026/08/03-thread-rolling-machine-bolt-production.webp) 02 **Thread rolling** Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch. Go / no-go ring gauges to ISO 965 tolerance class 6g. 3. ![Baskets of bolts staged for heat treatment](https://engineeringhardware.com/wp-content/uploads/2026/08/05-heat-treatment-baskets-black-bolts.webp) 03 **Heat treatment** Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it. Core hardness and tensile tested per lot to ISO 898-1. 4. ![Zinc plated bolts in a treatment basket](https://engineeringhardware.com/wp-content/uploads/2026/08/23-zinc-plated-bolts-treatment-basket.webp) 04 **Surface treatment** Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list. Coating thickness and neutral salt spray hours to ISO 9227. ## Frequently Asked Questions ### What standard are EPDM Rubber Well Nuts manufactured to? EPDM Rubber Well Nuts are manufactured to Trade series (rubber blind nuts). The dimensional values on this page follow that standard. ### Which sizes of EPDM Rubber Well Nuts does Engineering Hardware supply? The table on this page lists 5 sizes for EPDM Rubber Well Nuts, ranging from M3 to M8. Sizes outside the table can be quoted on request. ### In which materials are EPDM Rubber Well Nuts supplied? EPDM Rubber Well Nuts are supplied in matching property-class steel and stainless A2 / A4, with finishes including zinc plating, hot-dip galvanizing and black oxide. Choose material and finish to suit the load and the service environment for EPDM Rubber Well Nuts. ### How do I request a quotation? Use the parametric drawing on this page to set the exact configuration (size, material, finish) and click "Request this configuration" — a specialist from Engineering Hardware will respond within one business day.