Cool Hand Zirconia Ceramic Utility Knife Blades 6 Pcs,Sharp&Rustproof

I wouldn't use these for heavy duty utility, one side of the blade lasted for 2 sheets of drywall. Wasn't impressed, but cutting ground up rock with a thin ceramic blade was bound to be mangled up. However, cutting everyday things like paper & fabric, these excel. I use them for cutting leather, fabric, and cardboard, and I'm still using the same blade after trying to abuse it. Be careful, they are the type of sharp where you can cut yourself without feeling it.

I use my utility knife a lot, and I abuse it like my parents abused me. (That is to say, my knife definitely needs therapy.) Hopefully the photo attaches to the review, this one blade is ~5 months old and is used VERY regularly. I moved over to a ceramic blade wanting to try it out as I do not generally require razor sharp precision, I just need it to be sharp enough to cut straight-ish. I mostly am cutting up a lot of cardboard, plastic, tape, etc. I avoid using this on anything hard like a wire since it has a tendency to chip, use a metal blade for that. These blades are a little bit thicker than the metal ones, so be aware of that if the metal blades are already very snug in your knife. I was probably flipping my metal blades at least every 2 weeks, it took me about 3 months to need to flip this one. It was still sharp enough, but the chips in the blade were getting a bit too bad.

These blades are amazing! I bought them specifically to slice up cardboard boxes for the recycle bin. My name-brand metal blades dull very quickly on heavy cardboard. THESE blades last a LONG time! In fact, after several months, I'm still on my FIRST blade! If I look really closely, I can see tiny chips all the way down the blade--but the blade still cuts like new. I am truly amazed! I was concerned they might be brittle, but I haven't broken one yet. (I still think it probably would not survive a fall onto concrete, while in the knife.)

Positives: Very Sharp blades and slice through most materials without any trouble. These are great blades for certain applications. Being ceramic they are non-metallic so great for added peace of mind when working near electrical. These also won't rust so they're great for working in wet environments. Cons: -These are NOT comparable to the SLICE brand ceramic blades. These are much sharper and WILL cut you with the slightest contact. -These are very brittle and prone to breaking. Do not even try to use them in any way other than slicing. Don't use them near hard materials as pieces will break off. And be very careful if handling near any materials that you can't risk tiny fragments falling into.

Great and very sharp blades. I keep this cutter in the well house to open salt bags. Regular blades don't stand up to salt like these do. Problem solved!

Bought specifically to slice up Amazon boxes for the trash. Came out of the box like gangbusters. First few slices were amazing. Pooped out pretty quickly though on the first box (maybe 20" x 40"). After that it wasn't any better than the steel blades from the big box store. Looks neat.

First — Ceramic blades aren't for everyone, and they aren't for all situations. They have real benefits (a sharp edge that can last longer) but they come with real compromises too (serious brittleness). I've tried these with 5 different utility knives. They broke prematurely in almost all of them, with the crack starting to form near the two cutouts at the top of the blade. The Oknife U1 is the only knife I've found that is able to grab onto the blade without fracturing it.

I first(and last) purchased these on Feb 26, 2023. Me and my girlfriend both use these. I bought the six pack and currently have 1 left brand new, 1 used and we both have 1 in our box cutters. Of the 6 pack, we still have 4. My girlfriend used it incorrectly and broke one blade the first day she used it. 6 months in, I broke a blade dropping my box cutter. Today I just chipped on end of one side of the blade. I'd say the 15 dollars more than paid for itself. I use to use dewalt carbide which I can get a 5pk for about 6 bucks. Changing the blade bi-weekly, I would have spent around $25 in a year. Nothing crazy to break the bank, but I can easily see these lasting me at least until Feb 2025, meaning I would have spent another $25, making these come out as saving me $35 bucks. If you're careful with your tools, I can easily see this lasting a very long time.