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This 20-piece set of black powder-coated aluminum extrusion L-brackets includes 40 M5 screws and a wrench, crafted from electrophoresis zinc alloy for exceptional rust and abrasion resistance. Designed to fit 20 series 6mm slot aluminum profiles, these concealed corner braces provide robust, hidden support ideal for professional-grade 3D printers, CNC routers, robotics, and industrial framing projects.











| ASIN | B08D6T9CGN |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #2,565 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #2 in Hardware Brackets |
| Customer Reviews | 4.5 4.5 out of 5 stars (994) |
| Date First Available | July 17, 2020 |
| Finish | Powder Coated |
| Finish Type | Powder Coated |
| Included Components | 20 series aluminum extrusion l bracket., 2020 series m5 set screw. |
| Item Depth | 0.2362 inches |
| Item Package Quantity | 1 |
| Item Weight | 7.8 ounces |
| Item model number | 2020 series extrusion M5 |
| Manufacturer | Tongling Hardware |
| Mounting Type | Corner Mount |
| Part Number | Tongling-JC-20 |
| Product Dimensions | 1.02 x 0.37 x 1.02 inches |
| Size | 20pcs black with screws |
| Style | 20Pcs Interior Bracket with Screw |
| UPC | 796862233273 |
| Unit Count | 20.0 Count |
M**L
Strong, Precise, and Easy to Assemble
This corner bracket set is excellent quality. The aluminum extrusion brackets are sturdy and well‑machined, with clean edges and consistent sizing that make assembly smooth. The included T slot nuts and bolts fit perfectly, saving me the hassle of sourcing hardware separately. I used these for a DIY frame project, and the joints came out solid and square with no wobble. The finish looks professional, and the hardware tightened down securely without stripping. It’s clear these are designed with precision and durability in mind. For anyone working with 2020 series aluminum extrusion, this set is a reliable choice that delivers both strength and convenience. Highly recommend!
B**N
Well Made
Well made no burrs. Fit perfectly and made a solid connection between two bars.
D**I
Helped square the machine for smoother motion
I bought these for the Ender 5 I own. It's still in pieces at the moment but these corner brackets work exactly as specified. They helped me make the entire printer more square than before my tinkering. The Y axis motion is smoother due to being more square. Absolutely a breeze to use. They sit inside the frame, so they are not unsightly like the original corner brackets. Remember to use thread lock on the grub screws.
V**M
Tight fit
These work well and are sturdy for interior joints. But they fit quite tightly. I was mounting a cross bar between two pieces of extrusion and trying to slide it to align it properly, but even when fully unscrewed, these brackets are very hard to move.
D**N
works as advertised
great quality
C**O
It works well
Works well will my 2020 aluminum. It is sturdy and reasonably priced
S**T
Product is exactly as described!
Perfect. Product is exactly as described.
J**G
Simple => versatile!
I used these simple L brackets for a different application than they were designed for -- to create "platforms" or "ledges" on which I could support gutter guards against the back of the gutter. I know, kind of random. But they worked! And they're aluminum, so they won't corrode. Only product I found on Amazon that looked like it would work for this purpose.
Y**Z
Perfect at 20mm x 20mm, not like similar ones that stick out a few mm. That means the hole at the end of a 2020 extrusion lines up. I bought twice now.
A**N
J aimerais savoir si il y a des équerres plus grandes mais qui a 6 mm la même mesure mais plus long de chaque cote
D**Z
The flaws are fixable. The tube that goes over the bolt to keep from crushing the hinge is plastic - should be metal. Fortunately I had an appropriately sized metal tube in my scrap bin and cut a length to fit. Then, there is too much of a gap between the inner and outer tabs that would cause the outer tabs to clamp down unevenly. Fix is to use a thin washer between the inner and outer tabs on one side so everything starts out snug and nothing flexes when tightening.
C**S
Good quality and fits well
B**R
Work as described
Trustpilot
3 days ago
1 month ago