The cable areas in the clips for tubing diameters 1.0 inch and above are designed to hold 7-8 typical “SVT” power cords (UL-Type SVT, 3C/18AWG 300V, ~6mm in diameter).
The under-1.0 inch sizes are made to handle 4-5 SVTs.
“Well yeah, but my cables are HEAVY!” The thing to remember is that no component is ever infinitely strong, nor will anything (besides time itself) last forever. The same is true with 4CELNK-YR clips. There is some large amount of force that will break them. I haven’t reached it yet, but it’s not at all impossible to yank on a cable and pull it out of the clip. (If you’re going to be violently pulling the cables, then maybe stick with tie-wraps)
From what I’ve been able to tell, “a couple pounds” (~1kg) is just fine as far as holding strength. I might be inclined to add more bands (5-6 instead of 3-4) up to about 5 pounds (2.2 kg), but beyond that weight you should consider adding more clips. A typical “good” straight run of 6+ ethernet cables would normally have a clip about every 3-4 feet (~1 meter) or so, more if the cables need more support.
But, beware: if you put only one clip every 8 feet, and expect it to hold 20 pounds, that will very likely end in disaster…and the warranty won’t cover it.