Looking for the best M4 brass insert to secure threads in your 3D prints? We’ve rounded up the top 10 options to help you achieve professional and reliable results with ease.
3D printing is an exciting world, but getting secure threads can be tricky. That’s where M4 brass inserts come in. They’re the secret weapon for strong, lasting connections in your prints.
These inserts are easy to install and work perfectly with plastic parts. They’re made of high-quality brass, so they’re durable and corrosion-resistant.
With the right M4 brass insert, your 3D prints will feel professional and reliable. Let’s explore the best options to take your projects to the next level.
List of Top 10 M4 Brass Insert For Secure Threads In 3D Prints
| Image | Title | Best For | Price |
|---|---|---|---|
![]() |
400 Pcs Zruosiniy Premium Brass Threaded Inserts Kit, M2 M2.5 M3 M4 M5 M6 Female Metric Knurled Insert Nuts, Heat Set Inserts for Plastic & 3D Printing Components |
This 400-piece brass threaded inserts kit is perfect for 3D printing enthusiasts, hobbyists, and professionals who need reliable, durable parts for their projects. It’s also ideal for plastic molding and repairs, offering secure, long-lasting results every time. |
|
![]() |
HANGLIFE Heat-Set Threaded Inserts, M4 Heat Set Insert for 3D Printing Components and Plastic Parts – Brass Metric Knurled Nuts (100 Pieces) |
This M4 heat-set threaded insert set is perfect for 3D printing enthusiasts and makers who want to add strong, reliable threads to their plastic parts. If you’re building anything from 3D printer components to plastic enclosures, these inserts will securely fasten your parts with ease. |
|
![]() |
ruthex M4 Threaded Inserts – 50 Pieces RX-M4x8.1 Brass Heat Set Insert for Plastic Parts – Metric knurled Nuts – Insert by Heat into 3D Printing Components |
This 50-piece set of M4 threaded inserts is perfect for 3D printing enthusiasts and makers who want to add strong, reliable threads to their plastic creations. If you’re working with PLA, PETG, ABS, or other thermoplastics, these lead-free brass inserts will give your projects a professional and durable finish. |
|
![]() |
Yaocom 300 Pcs M4 Threaded Inserts M4 x D6 x L6 Heat Set Inserts Brass 3D Printing Knurled Metric Nuts for Plastic, 3D Printing Components |
This 300-piece set of M4 brass threaded inserts is perfect for 3D printing enthusiasts and makers who need reliable, easy-to-install fasteners for their projects. Get secure, long-lasting connections in plastic with these high-quality, knurled nuts. |
|
![]() |
Kadrick 520Pcs M2 M3 M4 M5 Threaded Inserts Assortment Kit for 3D Printing Components, Metric Brass Knurled Nuts, Insert by Heat into Plastic Parts |
This Kadrick Threaded Inserts Assortment Kit is perfect for 3D printing enthusiasts. It’s ideal for adding strong, reliable threads to plastic parts. |
|
![]() |
100Pcs Pofsnnx M4 Threaded Inserts, Brass Heat Set Insert for Plastic and 3D Printing Components, Metric Knurled Nut Classification Combination Kit(M4xL4xD6, M4xL8xD6) |
This 100-piece brass insert kit is perfect for 3D printing fans and DIY lovers. It’s great for fixing plastic parts and making strong connections. |
|
![]() |
Aoserge 100Pcs M4 Brass Heat Set Inserts – Premium Knurled Threaded Nuts for 3D Printing, Plastic Parts & DIY Projects, High-Temperature Resistant, Easy Heat Installation(M4x6x6mm) |
These M4 brass heat set inserts are perfect for 3D printing enthusiasts, DIY makers, and anyone needing strong, reliable fasteners for plastic parts. They offer easy installation and long-lasting durability for all your projects. |
|
![]() |
Kadrick 420Pcs M3 M4 M5 Threaded Inserts Assortment Kit for 3D Printing Components, Metric Brass Knurled Nuts, Insert by Heat into Plastic Parts |
This Kadrick Threaded Inserts Assortment Kit is perfect for 3D printing enthusiasts who need a reliable way to add threads to their projects. It’s ideal for anyone working with plastic parts and looking for strong, secure fixation. |
|
![]() |
FFVRVSS 320+6Pcs M2 M2.5 M3 M4 M5 Premium Brass Threaded Inserts, Metric Brass Knurled Nuts Assortment Kit, with Heat Set Insert Tool, for Plastic and 3D Printing Components, All-in-one |
This all-in-one kit is perfect for 3D printing enthusiasts and DIY lovers. It’s also great for anyone working with plastic parts, like automotive or electronics projects. |
|
![]() |
uxcell Knurled Insert Nuts, 50pcs M4 x 4mm L x 6mm OD 3D Printing Brass Nuts Female Threaded Inserts Brass Heat Set Insert Embedment Nuts |
These uxcell Knurled Insert Nuts are perfect for 3D printing enthusiasts, electronics hobbyists, and professionals who need reliable, durable fasteners for their projects. They’re easy to install and work great for tight fixing in plastic, computer, and electronic products. |
Detailed Reviews
Discover the top 10 M4 brass inserts for secure threads in your 3D prints. Each product is carefully reviewed for quality, durability, and ease of use. Whether you’re a beginner or a pro, this guide helps you find the perfect fit for your projects. Start here to upgrade your 3D printing with confidence and precision.
1. 400 Pcs Zruosiniy Premium Brass Threaded Inserts Kit, M2 M2.5 M3 M4 M5 M6 Female Metric Knurled Insert Nuts, Heat Set Inserts for Plastic & 3D Printing Components

This kit has 400 brass threaded inserts. They are strong and long-lasting. Works great for plastic and 3D prints.
It comes in 15 sizes from M2 to M6. All pieces are organized in a box for easy use.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This 400-piece brass threaded inserts kit is perfect for 3D printing enthusiasts, hobbyists, and professionals who need reliable, durable parts for their projects. It’s also ideal for plastic molding and repairs, offering secure, long-lasting results every time.
Ready to Purchase?
2. HANGLIFE Heat-Set Threaded Inserts, M4 Heat Set Insert for 3D Printing Components and Plastic Parts – Brass Metric Knurled Nuts (100 Pieces)

HANGLIFE Heat-Set Threaded Inserts are designed to fit perfectly in your 3D printed parts. They are easily installed using heat or ultrasound for a strong and secure hold. These inserts help make your 3D printed components more durable.
Made from high-quality brass, these inserts are corrosion-resistant and provide excellent thermal conductivity. Their robust construction ensures they will not break or deform easily, making them a reliable choice for various uses.
This set includes 100 inserts with M4 internal thread, each 6mm in width and 6mm in length. It works with PLA, PETG, ABS, and other thermoplastics. These inserts are perfect for different projects. They are a simple and effective solution.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This M4 heat-set threaded insert set is perfect for 3D printing enthusiasts and makers who want to add strong, reliable threads to their plastic parts. If you’re building anything from 3D printer components to plastic enclosures, these inserts will securely fasten your parts with ease.
Ready to Purchase?
3. ruthex M4 Threaded Inserts – 50 Pieces RX-M4x8.1 Brass Heat Set Insert for Plastic Parts – Metric knurled Nuts – Insert by Heat into 3D Printing Components

Upgrade your 3D printed parts with ruthex M4 Threaded Inserts. These brass nuts offer a firm hold and are easy to install using heat or ultrasound. They are designed for long-lasting performance in various plastics.
This practical set includes 50 pieces of RX-M4x8.1 inserts, perfect for your next project.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This 50-piece set of M4 threaded inserts is perfect for 3D printing enthusiasts and makers who want to add strong, reliable threads to their plastic creations. If you’re working with PLA, PETG, ABS, or other thermoplastics, these lead-free brass inserts will give your projects a professional and durable finish.
Ready to Purchase?
4. Yaocom 300 Pcs M4 Threaded Inserts M4 x D6 x L6 Heat Set Inserts Brass 3D Printing Knurled Metric Nuts for Plastic, 3D Printing Components

Yaocom M4 Threaded Inserts come in a bulk package of 300 pieces. They are perfect for 3D printing, electronics, and more. Each insert is made from quality brass material.
These inserts are easy to install using heat or ultrasonic methods. They fit smoothly without needing extra holes. Their precision construction ensures secure fixation every time.
The outer diameter is designed to grip tightly. Once in place, they stay firmly without slipping. These inserts are durable and long-lasting for all your projects.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This 300-piece set of M4 brass threaded inserts is perfect for 3D printing enthusiasts and makers who need reliable, easy-to-install fasteners for their projects. Get secure, long-lasting connections in plastic with these high-quality, knurled nuts.
Ready to Purchase?
5. Kadrick 520Pcs M2 M3 M4 M5 Threaded Inserts Assortment Kit for 3D Printing Components, Metric Brass Knurled Nuts, Insert by Heat into Plastic Parts

Elevate your 3D printing projects with the Kadrick M2-M5 Brass Threaded Inserts. These knurled nuts offer a superior grip for your plastic parts.
These inserts are perfect for 3D printing. Simply heat them into plastic for a secure fit.
The kit includes common sizes from M2 to M5. They are made of high-quality brass for durability. Each size is clearly labeled for easy use.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This Kadrick Threaded Inserts Assortment Kit is perfect for 3D printing enthusiasts. It’s ideal for adding strong, reliable threads to plastic parts.
Ready to Purchase?
6. 100Pcs Pofsnnx M4 Threaded Inserts, Brass Heat Set Insert for Plastic and 3D Printing Components, Metric Knurled Nut Classification Combination Kit(M4xL4xD6, M4xL8xD6)

Upgrade your projects with these 100Pcs Pofsnnx M4 Threaded Inserts. They are made of premium brass for a strong, reliable hold. These inserts are easy to install in plastic and 3D-printed parts.
These knurled nuts grip plastic tightly, preventing loosening. They offer high pull-out resistance for secure fastening.
Perfect for 3D printing and plastic assembly, these inserts are a cost-effective value pack. Get them for your next project!
| Pros | Cons |
|---|---|
|
|
Perfect For:
This 100-piece brass insert kit is perfect for 3D printing fans and DIY lovers. It’s great for fixing plastic parts and making strong connections.
Ready to Purchase?
7. Aoserge 100Pcs M4 Brass Heat Set Inserts – Premium Knurled Threaded Nuts for 3D Printing, Plastic Parts & DIY Projects, High-Temperature Resistant, Easy Heat Installation(M4x6x6mm)

Upgrade your projects with Aoserge M4 Brass Heat Set Inserts. Get 100 premium threaded nuts for long-lasting durability. They are high-temperature resistant and easy to install.
These inserts are perfect for 3D printing and plastic parts. Their knurled design provides a strong grip and prevents slipping.
Use them for DIY projects, woodworking, and more. These versatile inserts offer reliable fastening for all your needs.
| Pros | Cons |
|---|---|
|
|
Perfect For:
These M4 brass heat set inserts are perfect for 3D printing enthusiasts, DIY makers, and anyone needing strong, reliable fasteners for plastic parts. They offer easy installation and long-lasting durability for all your projects.
Ready to Purchase?
8. Kadrick 420Pcs M3 M4 M5 Threaded Inserts Assortment Kit for 3D Printing Components, Metric Brass Knurled Nuts, Insert by Heat into Plastic Parts

Upgrade your 3D prints with Kadrick’s M3, M4, and M5 threaded inserts! These brass nuts are designed to be heated into plastic parts, giving you strong, reliable threads.
Get the most common sizes for your projects. This kit includes plenty of M3 inserts, plus M4 and M5 for wider use. They come in heights from 3mm to 12mm.
These knurled inserts offer superior grip over plain ones. Made from high-quality brass, they resist heat and corrosion. Plus, each size is clearly labeled in a handy plastic box.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This Kadrick Threaded Inserts Assortment Kit is perfect for 3D printing enthusiasts who need a reliable way to add threads to their projects. It’s ideal for anyone working with plastic parts and looking for strong, secure fixation.
Ready to Purchase?
9. FFVRVSS 320+6Pcs M2 M2.5 M3 M4 M5 Premium Brass Threaded Inserts, Metric Brass Knurled Nuts Assortment Kit, with Heat Set Insert Tool, for Plastic and 3D Printing Components, All-in-one

This all-in-one kit is your ultimate solution for 3D printing and plastic projects. It includes 5 common brass threaded insert sizes (M2, M2.5, M3, M4, M5) and an upgraded heat set tool. Get everything you need in one simple purchase.
Crafted from top-tier brass, these inserts offer superior strength and durability. They resist rust, bending, and breaking, ensuring long-lasting, secure fastenings. Enjoy rock-solid connections that stand the test of time.
The precision threading and knurled design guarantee a super-tight grip. Everything is clearly labeled and organized for easy access.
| Pros | Cons |
|---|---|
|
|
Perfect For:
This all-in-one kit is perfect for 3D printing enthusiasts and DIY lovers. It’s also great for anyone working with plastic parts, like automotive or electronics projects.
Ready to Purchase?
10. uxcell Knurled Insert Nuts, 50pcs M4 x 4mm L x 6mm OD 3D Printing Brass Nuts Female Threaded Inserts Brass Heat Set Insert Embedment Nuts

Meet the uxcell Knurled Insert Nuts, your new go-to for secure 3D printing and more. These nuts are made from durable brass for lasting strength. They offer excellent heat and corrosion resistance.
Installation is a breeze with their guide design, no special tools needed. The embossed outer diameter creates a strong grip, ensuring they stay put. They provide reliable torsion and tension.
Perfect for 3D printing, injection molding, and electronics. Get tight, stable fixing for your projects.
| Pros | Cons |
|---|---|
|
|
Perfect For:
These uxcell Knurled Insert Nuts are perfect for 3D printing enthusiasts, electronics hobbyists, and professionals who need reliable, durable fasteners for their projects. They’re easy to install and work great for tight fixing in plastic, computer, and electronic products.
Ready to Purchase?
Buying Guide
M4 brass inserts are a game-changer for 3D printing projects. They make your prints strong and reliable.
Buying Guide: Best M4 Brass Inserts for Secure Threads in 3D Prints
When choosing M4 brass inserts, consider these key factors:
-
Material Quality: Look for high-quality brass that is durable and corrosion-resistant. This ensures long-lasting performance.
-
Size and Fit: Ensure the inserts are M4 size and fit your 3D printed parts perfectly. Check the outer diameter and length for a snug fit.
-
Installation Method: Decide between heat or ultrasound installation. Both methods provide a secure hold, but heat is more common and easier.
-
Quantity: Choose a pack size that suits your needs. Options range from 50 pieces to 400 pieces, depending on your project scale.
-
Knurled Design: Opt for inserts with a knurled outer surface. This design provides a strong grip and prevents slipping.
-
Compatibility: Ensure the inserts work with your materials, such as PLA, PETG, or ABS. Check for compatibility with plastic parts and 3D printing components.
-
Organized Packaging: Look for kits with clearly labeled and organized inserts. This makes it easy to find the right size when you need it.
-
Value for Money: Compare prices and quantities to find the best deal. Some kits offer a cost-effective value pack for multiple projects.
With these factors in mind, you’ll find the perfect M4 brass inserts to take your 3D prints to the next level.