Zeberoxyz 10pcs Black Straight Line Connector Length 3.9inch Joint Bracket with M5 Screws for 2020 Series T Slot 6mm Aluminum Extrusion Profile (2020 Series Straight Brackets-Black)

Not a lot to say, they worked well to join 2 pieces of Aluminium profile together, Slide them in tighten the grub screws down firmly and neither piece budges. 5 Stars!

Was easy to fit, extended the 2m limit in the chanel. great , simple product, probably only need to use 3 out of 4 parts for each joint to leave the top slot free for sliding in connectors. so you can get 4 joints out of 3 packs.

I have snapped one hence the 4 stars. Was nice to find something easy to use to make angles. The grubs are better than the ones that came with the profile. But one did snap pretty easy.

Some good, some not so good. Had to knock two of the fittings in due to the poor profile and consequently broke two of the fittings 😬

This pack of L brackets arrived in a small plastic bag with the grub screws separated into another bag inside with the matching Allen key required to fix them in place. There were exactly 20 of the brackets and there were 43 of the grub screws, giving you a couple of spares for when you inevitably drop one. The brackets are coated in a durable black coating that matches black anodised extrusions quite well. They’re all made to a nice standard and I wasn’t able to spot any problems across the entire batch with the black coating, squareness or threading on the holes.These L shaped corner joints are a super simple way to join pieces of aluminium extrusion together if you’re working on something using 2020 series, as long as you have access to the internal 90-degree corner. I gave them a quick test when they arrived using some spare 2040 and 4040 extrusion and had no issues forming a robust and square T shaped connection between the pieces using a couple of these L joints. Then I spent some time verifying that each of the brackets was truly 90 degrees with my machinist’s square. Each one was bang on 90 degrees when I checked the flat surfaces that push against the slot in the extrusion. Not one of them had any noticeable deviation from this and I couldn’t get any of them to wobble against the 90-degree corner of my square at all.I wouldn’t necessarily rely on these brackets alone on being the easiest, most cost-effective, or the most rigid way to build up something like a 3D printer frame. With that said, it is a very quick and convenient option that anyone can use without having to drill or tap holes. Ultimately, it is another option that exists and may solve a unique limitation or design problem during an extrusion based project. To be honest, if you squared up the connections properly when you’re working with these, there is no reason you can't end up with something square enough to make a printer frame out of.Something to keep in mind is that due to the way these attach to the extrusions, you’re going to be leaving pretty deep gouges behind if you ever remove the brackets. To get them to hold tightly enough to support any weight or add rigidity, you have to crank down hard on the grub screws to give them a strong enough hold on the extrusion. You can see what I mean in my photos of the extrusions after removing the L brackets.These are much better than I really expected them to be, the only minor issue I have is that the price is very expensive for 20 of them. Other than the cost being significantly higher than I believe it should be, these are an easy product to recommend.

Good pack of joint brackets though they're a bit smaller than I expected.We'll still be able to use them for the intended use of strengthening a piece of flat pack furniture that hasn't coped well with being dismantled for a house move.