30-Pack BINZZO Sliding T Slot Nuts 2020 Series M5: Nickel Plated Carbon Steel Half Round Roll-in Sliding 6mm Slot Aluminum Profile Accessories for 20 x 20 Series T Slot Aluminum Profiles Review

All dimensions except M8 hole designation are wrong! It does not fit in the 8mm T-slot! The slot on the profile I use is 8.4mm and doesn't even slip off the end.

I bought it for a 40x40 profile with an 8mm groove. The description says it's 8mm wide, so it fits in the slot. They are actually 9.82-9.83mm wide so they can't fall into the slot. The quality seems to be normal, but I never managed to use it for the reason mentioned above.

They do not fit size 40 profiles Look at the pictures, they are too big to rotate 90 degrees. and therefore not properly aligned in the slot. Instead, any interference in the center will push the nut against the edges of the slot and deform the slot. I will send them back.

T-Nuts insert and lock into 45 Series extrusion as intended. They don't have a locking mechanism so they slip as soon as you put them in. I first screwed in the T-nut and then tightened it enough that the fastener hooked into the groove of the aluminum profile and stayed.

These are sliding blocks, of course. They go well with the 2020 extrusions for my 3D printer. They are gripping and addictive as you would expect, so no design issues. The parts appear to be consistent and properly deburred (or maybe they're just well finished immediately after casting?). That's all.

There have been several reports of the nut 4040 being wrong width. You are correct, please see my photo. There is no doubt what size they should be as the size chart is clear. My project is now on hold because this company is not listening. It is unforgivable that I now have to return them.