Shun knives—polished Japanese steel—have gradually fallen into a state of neglect-induced impotence under my watch, and I’m the only one to blame. I need to sharpen them—not a quick tango with the honing steel; we’re talking whetstone territory. The thing is, I’m hesitant to venture there. Not only will I almost certainly scratch the sh*t out of the beautifully crafted steel, but I’m also not certain I have the skill to sharpen them correctly in the first place.

I could bring them to a professional, sure, but the only thing I love more than slicing vegetables is not doing the 40,000 chores I’ve been meaning to get done for years. Who’s got the time? Or the patience? That’s rhetorical—if you do, I don’t want to hear about it. So, what’s a knife-loving procrastinator like me to do?

There’s only one solution: I must go ultrasonic.

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Seattle Ultrasonics C-200

The C-200 ultrasonic chef’s knife is more than just a gimmick, but will only be noticeable with certain cuts and food items.

• Can slice razor thin
• Takes less force to cut certain food items
• Nice steel, ultrasonic or not

• Ultrasonic feature isn’t noticeable on everything you cut
• A bit bulkier than your average knife
• Not a kitchen gadget most people really need
• Pricey at $400

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Gotta go fast

Obviously, I could get my knives sharpened, but this is Gizmodo, and where’s the fun in a whetstone when you can just swap your old-fashioned steel for something newfangled like Seattle Ultrasonics’ $399 C-200 ultrasonic 8-inch chef’s knife? This is a gadget, I’m happy to say, that’s as ridiculous as it sounds.

It’s a knife made from Japanese AUS-10 stainless steel that incorporates a commercial manufacturing technology. It vibrates the blade of the knife 30,000 to 40,000 times per second, creating microscopic movements meant to assist your cuts. Seattle Ultraonics claims that this method of cutting (which only existed in factories prior to the C-200) can reduce the amount of force needed to slice by as much as 50%. Not only that, but the ultrasonic element is also designed to make a dull blade feel sharper, which is great for knife-sharpening procrastinators like myself.

It sounds like one of those gimmicks that’s too good to be true, and at first, I would have agreed with that assessment… until I didn’t.

The C-200 does work, though maybe not in a noticeable way for everything all the time. In my experience, the innovation of at-home ultrasonic cutting is situational. You’re not going to notice it cutting everything all the time, but when you do notice it, it’s pretty sick.

What’s for dinner?

So, what should you cut with the C-200? Tomatoes. You should cut tomatoes. This is arguably one of the first things that I really noticed the effect of the C-200 on, mostly because of the nature of the fruit. Tomatoes, you see, have a membrane, and most people with dull knives have probably encountered what happens when you mix your sad, under-loved knife with a tomato membrane—things get a little dicey, though not in a fun way. Cuts become coarse, and you end up applying too much force to the tomato in order to compensate, which makes cutting more dangerous and a lot less precise. Not with the C-200, though.

Seattle Ultrasonics says that, to test the knife’s performance against tomatoes, you can simply tilt the knife on the fruit, press the button on the knife, and watch as the blade sinks in. I tried this, and it works… sort of. You still have to apply some force to get the C-200 to sink in, but not much, and not nearly as much as you would with a regular knife. It’s also not just the newly sharpened blade playing tricks on me.

I tested cutting a tomato in all sorts of ways, both with the ultrasonic feature activated and not, and there is a noticeable difference when you’re smashing that ultrasonic button. Not only does it make entry into the cut easier, but it makes slicing thin a lot smoother. I tried cutting crossways to see how thin I could get a tomato slice, and the ultrasonic cut was significantly thinner—you can make paper-thin slices if that’s your thing. It’ll be great for that dreamcatcher made of tomatoes you’ve been meaning to craft.

Tomatoes aren’t the only place where the C-200 shines. I find the knife to be particularly efficient at cutting meat, both cooked and uncooked. Slicing raw chicken, for example, felt particularly smooth when I butterflied a breast using the feature. Carving a cured hunk of ham was also noticeably much easier with the button pressed than without. Cutting crusty bread (a baguette) also felt easier, requiring a bit less force, with ultrasonic power, which is nice considering you’re typically supposed to use a serrated knife for that.

Basically, if there’s a situation where a dull knife might get bogged down, the C-200 might perform better, and maybe even better than a sufficiently sharp regular blade. I say “might” and “maybe” in this case, because some things that Seattle Ultrasonics says are meant to be noticeable on the C-200 aren’t.

One thing I was excited to test out was cutting through thick, creamy stuff like cheese or butter. According to Seattle Ultrasonics, the C-200, since it vibrates while you slice, should slide through those food items more easily and with less food sticking to the blade. After slicing up quite a bit of cheese and some butter, though, I can’t say I noticed a huge difference. Maybe there was slightly less stickage, but not enough for me to declare the C-200 a revolution in butter cutting.

As long as we’re talking about being underwhelmed, it’s worth noting that there are times (outside of butter and cheese) where you’re not going to notice much at all. Chopping onions as I normally do, for example, felt mostly the same with the ultrasonic button activated and not activated, and cutting fruits like apples and pears was almost indiscernible from regular slicing, as was slicing oyster mushrooms.

I did smash some garlic with the flat side of the C-200 as well, and the knife didn’t feel like it was going to break or anything, which was nice, though I should hope a knife in this day and age is sturdy enough to smash garlic.

Your satisfaction will depend largely on the health and quality of your current knives at home, too. If you’ve got a tip-top chef’s knife that you love to cut with (especially a Japanese one with a steeper angle than a “Western” knife), then the C-200 is going to have tougher competition. If you’re like me and are rocking less-than-ideal steel, then this blade may seem like a revelation. I’m really curious how the C-200 will fare over time, since Seattle Ultrasonics says that its tech can make a dull knife feel sharper, but wear and tear doesn’t happen that fast, so maybe I’ll save that question for a later date.

One sec, I have to charge my knife

There is no getting around the fact that the C-200 is a knife with a battery in it. I can’t say that I encountered any problems with that fact, but it obviously adds a new layer to knife ownership. One of those layers is that the handle is much thicker than most chefs’ knives of a similar size. I can’t say that it makes the C-200 feel unwieldy or anything, but I found that it makes it a little more clunky than a regular blade, and how much of that clunkiness you feel will depend on the size of your hand and your preferred knife feel. Speaking of knife feel, you cannot feel the vibrations of the blade while you’re holding it, which is good since having a knife wildly flail about when you’re cutting is a safety hazard.

There’s a little bit of awkwardness with having to press a button while you slice things, but all things considered, Seattle Ultrasonics did put the button in an alright spot. I tried holding the knife in various ways, including by just gripping the handle like a caveman, but luckily it’s designed to be gripped as you would any other chef’s knife, which, for the uninitiated, is by choking up on the blade and punching it between your thumb and the knuckle/side of your index finger. If you’re not already holding your knife this way, you should. Thank me later.

The C-200 obviously has a battery, too, which can be popped off from the end and charged via USB-C. I have to say, prying a battery off a handle with a very sharp blade attached to it isn’t the most comforting activity in the world since it does involve using some force, but I guess you get used to it. Just please exercise caution when you take the battery out if human fingers aren’t on tonight’s tasting menu. If you don’t want to pry the battery out, you can use a charging block sold by Seattle Ultrasonics that also wirelessly charges the knife, but that’s an extra $150. Most of the time, I’d rather risk losing a pinky than shell out an extra $150, though. The company does sell a bundle that costs $499, saving you $50. An extra battery also costs $80 a pop if yours stops holding a charge or you want spares.

Battery life, by the way, is seemingly solid. Seattle Ultrasonics says you’ll get 20 minutes of continuous ultrasonic slicing and dicing, which is plenty if you’re just holding down the button for short durations while you slice something. I didn’t really encounter any battery life woes while using the knife over the course of the week, but it will depend on how much you cook and how long you’re cooking. I’m curious how the battery holds up long term and with continuous use, but that’s hard to say without using the C-200 for a longer period.

Oh, and let’s talk about washing. While Seattle Ultrasonics says you can rinse the blade in water as you would any other knife, you cannot submerge it. If you do submerge it, it’ll be okay for a few seconds, but you’re supposed to promptly take the knife out of said liquid and dry the outside and inside of the battery compartment with a dry cloth. You should not put the C-200 in the dishwasher, nor should you do that for any knife you respect. You cannot use the C-200 on metal or glass cutting boards, but, like… why are you using those to begin with? They’re not good for your knives or your soul (God told me so).

A cut above?

Let me be very clear: you do not need an ultrasonic knife. Sharp knives have been holding it down in kitchens at home and in Michelin-starred restaurants for quite some time, and I don’t think the C-200 is going to change that.

That being said, there is something nice about cramming ultrasonic technology into an at-home knife. Maybe you’re really intent on getting the thinnest possible slices; maybe you don’t want to prolong inevitable knife maintenance; maybe you have mobility issues and need a little assist from time to time. In those cases, I can see the C-200 being a useful knife to have.

For most people, though, regular knives will do. Most kitchen gadgets aren’t really made to be revolutionary, though. Do you really need a sous vide machine? An air fryer? A smart meat thermometer? Probably not, but you might want them all the same. And who am I to stop you from stepping into the microscopically vibrational future, even if that future only feels real for some things, some of the time?