Sorry, I do not have the box or the label any longer. As I said in my post, this was a pre-final packaging unit (not yet for sale to the general public as Cable Matters is waiting for the final packaging, official HDMI ULTRA HIGH SPEED HOLOGRAM TAG, etc. before they can sell this cable to the general public, so I suspect they will be available very soon.)
I have a projector installation going in where the HDMI wire was difficult to route around steel beams, etc. through a finished ceiling, and I wanted some future proofing. I am using this cable between a JVC RS3000 projector and the Denon AVR-X6700H Receiver. The Denon has a true 8K output, but the JVC is only native 4K (with 8K E-shift upscaling).
Again, I simply wanted a future proof cable for the next projector given the wiring difficulty. If you look at some of the newer LG 4K TVs available, you will find that they are are also really 40Gbps, not 48Gbps
LG’s 2020 4K OLED And LCD TVs Don’t Support Full 48Gbps HDMI 2.1 Per this article, 40Gbps implies 10-bit (rather than 12-bit) 4K at 120Hz with RGB 4:4:4 chroma sampling. I am not sure in the real world what this means and whether any of us will be able to tell the difference on real 8K equipment, with real 8K sources from real seating-to-screen distances. So, I am not surprised the Denon cable test is matching the 40 Gbps 4K LG TV specs, and this may be due to the currently available 4K (and 8K) processing chip designs or other arcane reasons.
The best source material I have are some 4K Ultra HD Discs (Planet Earth II and Blue Planet) so more on that later.
On the bandwidth testing, I was able to test a storage container full of old HDMI cables and in my testing, the Denon consistently passed (or failed) the cables uniformly and their speed capabilities measured consistently the same after three tests for each cable. There are some old youtube videos out there where the Denon cable test appears inconsistent or inaccurate, but I believe these were done 1) with older non-updated Denon firmware and 2) in a few of the videos I have seen, the Denon unit was not turned off between tests, which does not allow for a fresh digital handshake clean start at the beginning of each test. Just FYI, interestingly, some of my older cables consistently pass an 8K signal, but these were all shorter cables. The only 10M cable that could consistently pass the 8K test on my Denon was the Cable Matters 300047 model.
I will post again with my impressions of cable performance and screen shot photos (of 4K images) using this cable. My equipment installation will be completed in the next few days, so I look forward to this part of the test!
Update 3_18_21:
OK, now I have some iPhone photos of my projector screen using a JVC RS3000 projector on a 135" Stewart Filmscreen StudioTek 130 G4. (I even had a light on in the back of the room when these photos were taken.) This Cable Matters HDMI cable really rocks, and it is now on Amazon in the 10M size for $99. Having used it for several intensive weeks now, I can now highly recommend it! First photo of Cheetah face is from an 8K youtube video streamed via 4K firestick then upscaled via 8K output on Denon to 8K e-shift JVC RS3000 projector.
Amazon product ASIN B08GMC7C91