UT1 Ceramic Utility Blade Razor Sharp 6pack

I bought some for me, some for friends. Everyone is impressed

I have purchased all kinds of blades for utility knives over the years, but these are by far sharper and hold their edge longer than any metal blades I have used. I know how, and have sharpened many metal utility blades, but they seem to dull out quickly. So far, these have remained very sharp in my use. The only downside that I know of with ceramic blades (all ceramic, not just these) is that they can be brittle. I am very satisfied with these blades, and will definitely purchase more of these when needed.

The blades break at any side load but the edge lasts a long time if you do not twist the knife.

The blade cuts through cardboard without even trying. Even the thickest corrugated is no Mach for this blade.

These blades are plenty sharp enough, and the seem to be quite durable. But they seem to be a little bit thicker than the metal blades that you normally get with different box knives. I've had to really work on them to replace the metal blades with these ceramic ones, and I've had one knife that worked perfectly fine with metal blades, but when I put one of these into it, it really didn't want to retract or extend the blade like it was supposed to. It seems that maybe the "waist" of the blade is a bit thicker than they are on the metal blades or some of the other ceramic ones, so it's catching on the side of the knife as you're trying to extend it. Overall, though, I've found these to be good, especially on the knives where you can fold out the blade, not use a spring mechanism to extend it.