2-Pack CR10 Z axis T8 Anti Backlash Spring Loaded Nut Elimination Gap Brass Nuts for Upgrade Ender 3 Ender 3s Ender 3 Pro V2 CR-10 Tornado 3D Printer 8mm Acme Threaded Rod (Nuts)

One of these didnt even fit so seems like size isnt very accurate for these things

Easy to upgrade from standard.

Quality was ok but caused z-axis binding. Nice idea, but the experiment does not work.

Pulled the z axis rods off and installed these. No problems with fitment. Not sure if a gimmick or a useful product, time will tell but quality seems good and install was a breeze.

Bolts dont line up on Ender 3 Pro. Essentially useless for my dual z set up. May try and swap for a new set, maybe it was a one off, otherwise the one star sticks for bad QA. Side note, on a test fit on the guide screw, it seems like this would lead to binding. Seems like the threads are off ever so slightly after a few twists you feels a good amount of resistance, then it lets off, then tight, then loose, etc etc. Again... could just be bad QA.

I bought two for my dual z setup 3D printer. The first I installed went on fine, and absolutely removed the z wobble I was experiencing on that axis. The second somehow wouldnt line up... I worked on it for a while, but none of the holes were working as the first, and I suddenly noticed the anti backlash nut end I was trying to install was overlapping much much more than the first, sticking out over both ends.. I took my calipers to it, and the first measured 26.5mm in length and the other was 24mm with closer spacing on all of the bolt holes. None of them lined up. The other reviews saying they dont fit were right, as were the ones happy, but I guess its a luck situation. I imagine if Id started with the smaller of the two I wouldnt have had a successful install and assumed they were just all wrong. Both bags were labelled identically. Same serial numbers and the same item name. Extremely disappointing. EDIT: I did hear back from the company on this. They dont seem to understand why they have two different sizes, and offered me a completely different one as a replacement. The one they sell that is a regular z gantry nut and Oldham combo, but that would leave me without an anti backlash solution. I came to some conclusions after measuring the parts, and also my OEM gantry z nut. They have two different sizes of Oldham couplers. They have ONE size of anti-backlash nut, that fits only that larger size of Oldham. The reason why both sizes of Oldham fit the OEM gantry (without anti backlash nut) is the slot allows wiggle room on the oem nuts, and as such both sizes of Oldham fits. As do the anti backlash nuts on their own. Theres slop enough to allow fitment of both. Both sizes of Oldhams do not accept the anti backlash nuts that they sell, as many reviewers have mentioned. They are too large for the smaller Oldham coupler they sell. Its a c**p shoot because you either need two of their smaller Oldhams to pair with your original nuts (the larger ones will not fit, as the holes are too wide), or if you want to pair them with their anti backlash nuts, you need the two larger Oldham couplers from them. They are unable to specify what you will be getting. If you get two smaller ones, you need to source different anti backlash nuts that fit, or use your OEM fitting. *shrug* A straight mess. This is what happens when people buy from the same manufacturers and repackage them. They dont know what theyre selling, and if a huge amount of them leak into the market, were dealing with them not fitting in bizarre combinations for potentially years.

Like many have mentioned, the thread tolerance is incorrect (smaller) and causes a lot of binding and noise. This is the one “upgrade” that’s really a downgrade. I removed them, and everything is nice a smooth again.

I own a Creality Ender 3 v2 and put these on as an upgrade. It makes a big difference. Just know that the top piece with the notch in it, the notch faces down to the bottom, there is a great video on All3dp.com, but they tell you to put this piece on opposite of what i said because they are using a different mfg. But the rest is the same.

Completely removed horizontal artifacts. Just installed these on a dual z axis ender pro with the ender sprite pro head. I can see the detail in each layer. It is just perfect. Used with super lube grease

So, I can’t say for sure that these things are working. But, they are tight and so are my lead screws so I think they are. They are probably one of those things that you don’t see working but know they are. Would buy again.