ruthex 1/4" Threaded Inserts - 20 Pieces RX-1/4“-20x12.7 Brass Heat Set Insert for Plastic Parts - Inches knurled Nuts - Insert by Heat into 3D Printing Components

Impressive. Worked very well, easy to press in. Threads nice and clean.

I have used Ruthex before. No problems. The inserts hold very well in #D prints. Recommended. Thanks.

I've never had any trouble setting these with my soldering iron. I don't use any additional tools, jigs, or presses. Pretty easy stuff They work well and don't come out. Big fan

Went through the pack in a week. Very high quality and the specs on the front are exact especially for 3d prints. Great value and they fit great and are very strong. I used them for an outdoors application and they are showing no wear or movement.

These heat inserts fit perfectly into one of my 3d prints.

Love having a variety so I can use what's needed for different projects. Lot better to screw into verses plastic. Makes a strong connection.

I carve poll ball into shifter ball and these insert worked great

Let me just say this—if you’re printing enclosures or mounts and not using threaded inserts like these… you’re playing life on hard mode. I’ve burned through enough 3D prints to know that tapping straight into PLA or PETG is like trusting a paper towel in a hurricane. That’s where these ruthex M3 inserts come in and save the day like some kind of tiny, brass-threaded Avengers. These things heat-set like butter. No deformation, no bulging, no “oops, pushed too far” drama. The knurling bites in just right, and they seat clean at the recommended temps. I used a Weller iron with a blunt tip, hovered around 210–220°C, and every single one went in textbook perfect. No cracking, no misalignment. They don’t back out when you unscrew either. I’ve tested that plenty—over-tightening, removing and re-seating a half-dozen times—and they still hold strong like it’s their first day on the job. And the RX series? 👌 These aren’t your dollar-store “sorta fits” inserts. These are precision made. Consistent sizing, clean threads, and they ship in a plastic box that doesn’t explode open like it’s trying to test your patience. What I Like: Insertions are clean, controlled, and oddly satisfying No burrs or malformed pieces—every single one was usable Threads hold torque like a champ, no pull-outs ruthex isn’t playing around—these are real-deal engineered, not sketchy mass-stamped junk What Could Be Better: Honestly? Include a small tool or press-fit guide for new users maybe. That’s all I got. Oh, and maybe a reminder that yes, they are hot after heat-setting (ask my thumb) TL;DR: If you’re printing anything that needs to be unscrewed more than once, stop relying on melted plastic holes and upgrade your builds. These ruthex M3 inserts are rock solid, heat-set clean, and make your prints look and feel pro. Your future self (and your screwdriver) will thank you.

Dobry produkt, w dobrej cenie, szybka wysyłka, jestem zadowolony

Good product

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品質がとても良く、樹脂への食いつきも抜群です。ネジの締め込みもスムーズで、ガタつきや緩みなどの問題はまったくありません。3Dプリント部品への固定にも安心して使える、高精度で信頼性の高いインサートです。

I use these in every single 3D printed enclosure I design and they are perfect. Just finished off a bag of M3's and I've ordered some M4 and M5