Ok, so the sweet spot for the temperature is between 50 to 70 C is what you meant right. Then maybe i just use the mobo provided heatsink and see if the temperature go between those range.
If you're talking about the ssd dimension it is 80 x 22 x 3.5 mm and the form factor is M.2 2280. As for the material i'm not sure but i just assume they made of metal.
I'm new to m.2 nvme ssd and i just bought adata ssd SX8200 Pro 2TB which included it's own heatsink and my motherboard is Z390 aorus pro wifi which also included it's own heatsink that they call thermal guard. There is not many info about each of these included heatsink. So which one is better...