Benchmade 51 Morpho Balisong Butterfly Knife 4.25" Satin D2 Plain Blade, G10 Handles


MSRP* : $350.00 | You Save* : $52.50 (15%)


BM51: 51 Morpho Bali-Song


Benchmade Knives raises the bar on Bali once more! A patented liner-sprung latch opens with a squeeze, yet locks open, too. Solid, machined slab construction is built on jeweled ti-liners. Heat-treated kicker pins keep things rockin’ hard and fast, and a practical blade shape is detailed out with a crowned blade spine. Others may get all the press, but Benchmade still owns the glory when it comes to Balis and the 51 proves it. Again.


  • Bali-Song with premium D2 tool steel blade
  • Black G10 handles with anodized Ti liners
  • Movable Ti carry-clip


  • Blade Length: 4.25"
  • Blade Thickness: 0.100"
  • Blade Material: D2 Tool Steel
  • Blade Hardness: 60-62HRC
  • Blade Style: Crown Modified Spear-Point
  • Weight: 3.30oz.
  • Clip: Tip-Up, Blue Anodized Titanium
  • Lock Mechanism: Bali-Song w/ Spring-Latch
  • Overall Length: 9.35"
  • Closed Length: 5.10"
  • Class: Blue
  • Made in USA

UPC Code: 610953133382

Pocket Clip
Pocket Clip Includes a pocket clip for easy accessibility and a more secure carry.
G10 Handles
G10 Handles Formed in a sheet under high pressure by combining fiberglass and an epoxy resin binder. These handles are lightweight and shaped to ensure a solid grip.
D2 Tool Steel
D2 Tool Steel This is a high carbon steel that is appropriate for use in hostile environments and is known for edge retention.
Made in USA
Made in USA This product is USA born and raised.
Benchmade 51 Morpho Balisong Butterfly Knife 4.25" Satin D2 Plain Blade, G10 Handlesrated 4.724 stars out of 5 (58 reviews)
4.7 out of 5 stars
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Benchmade 51 Morpho Balisong Butterfly Knife 4.25" Satin D2 Plain Blade, G10 Handles
rated 5 stars out of 5
Aug 25, 2020
Pros: Blade Sharpness, Handle Material, Overall Quality, Pocket Clip, Ease of Opening, Handle Feel, Weight, Lock Ease of Use, Blade Material
Cons: Weight, None
Perfect EDC Bali, Moderately Great Flipper
Mainly got this knife for flipping; I am an avid knife fan and have several knives I can already EDC so that wasn't the main reason why I got this knife. However due to its decently low weight (REALLY low for most balisongs) and its elegant design and size, it is a nice knife to have on you without getting in the way, as well as it being made of relatively good quality steel and being razor sharp out of the box. The G10 handles and latch for locking into an open position PLUS the minimalistic pocket clip seal the deal making this possibly the best butterfly knife you can carry on a day to day basis. When in the closed position it takes a good squeeze to pop open the spring latch, strong enough that it will never accidentally open in your pocket yet not to the point that you have to grip it with a Hulk fist. All around great quality knife although pricey if you are using it solely for every day cutting purposes.Now to the flipping aspect... the light weight of the balisong is way more complicated than being solely good or bad for the knife. Since I've been used to flipping heavier knives it took a little while to get used to this feather spinning in your hand. Since it is lighter there are times where there is less momentum to control, which is good since it won't cut your hand as deeply if you mess up, but bad when you are used to using momentum to control the flow of the flips. However the pivots are flawless out of the box and the blade flips smooth as butter; it also makes satisfying little clicks in action (unlike some of the more unpleasant clunkier sounds heavier balisongs make, which is just a small detail). Unfortunately if you are a serious flipper you're going to have to deal with handle play at some point and this knife is no exception. If you dont want your BM51 to have severe handle play after a fair bit of flipping it is recommended that you loctite or re-loctite the torx screws and the pivots once in a while.But all-in-all, great balisong for the price range. You won't know until you buy it.
Benchmade 51 Morpho Balisong Butterfly Knife 4.25" Satin D2 Plain Blade, G10 Handles
rated 5 stars out of 5
May 21, 2020
Pros: Pocket Clip, Blade Material, Handle Feel, Weight, Blade Sharpness, Lock Ease of Use, None
Cons: Weight
Excellent Quality; Be Careful
So, I'm relatively new to balis, but definitely not to knives. I've carried for decades and don't go anywhere without a good blade (except a gov't building or place where they're prohibited, of course). I didn't buy this specifically for flipping and I have no aspirations of being anything more than a fidget/hobby flipper. I wanted this as a fun/high quality edc addition to my regular carry complement. This is a high quality knife right out of the box. Fit and finish are top notch and the action is very smooth. The whole thing is very sturdy. The D2 tool steel is solid and made to last with some minor maintenance. For edc, I love the weight. It's a bit lighter feeling than my normal edc SOG Trident Tanto and I can barely feel it in my pocket if I'm around the house and wearing light shorts. The deep carry pocket clip is a huge plus for me and the easily operated lock lets me deploy it easily and put it away just as fast. The blade is literally razor sharp out of the box. I can shave hair off my arm with it, which admittedly is a little overkill for an edc (for me), but is definitely a "nice to have". As a tool, it's definitely useful, and a bit of a fun thing when you nonchalantly whip it out, cut whatever you need to cut, then flip it right back into your pocket and get the wide-eyed looks from people who had no idea you even had a knife on you, let alone that you can manipulate it well. (It probably makes me look like a criminal to some people, but that's not always a bad thing when you want to be left alone. My SOG's assisted opening mech has a similar effect when people think it's a switchblade.)On to the Bali part. As I said, I'm relatively new to the Bali world and have no major ambitions. I'm kinda fidgety (ADD) and having something with me to get that out of my system is helpful. I've been learning on a knockoff Alphabeast trainer, and the weight difference is astonishing. This will definitely take a while to get used to since the handles are so much lighter. The weight that I love as an edc makes it a little harder to flip since it doesn't work up the momentum as easily. I'll adjust eventually to all the extra motion I have to use, but it's definitely a consideration when I learn something new on the trainer and want to move to the live blade. As I said earlier, the blade is shaving sharp right out of the box, which is a double edged sword (pun intended). As an edc I can cut anything I need to, but when flipping it is super easy to slip up and need a band-aid. I bit the cuticle on my index finger in the first few minutes on a wrist pass using the bite handle to deploy the cutting edge out, something I've done dozens of times with my trainer with no issue (it's called a bite handle for a reason, right?). Being so sharp means that the cut was very clean and sealed up tight after a couple of minutes with direct pressure. The crowned rear edge and low weight also prevent bruising when I inevitably hit my knuckles harder than planned, which is not a thing with my trainer (it bruises every time). The learning curve is high, but that's expected with live blade work, especially when you're used to much heavier equipment.All in all, I'm very satisfied with the 51 Morpho. It's different from what I'm used to for edc, but that's not a bad thing. It's a much more precise tool than my regular tanto, I swear I could do minor surgery with this thing. It also forces you to be a more conscientious flipper since the super sharp blade can give you a clean, but very bloody cut with just a light tap. I'm sure I'll modify it in the future because that's just how I am, but for now, it's exactly what I was looking for.
Benchmade 51 Morpho Balisong Butterfly Knife 4.25" Satin D2 Plain Blade, G10 Handles
rated 5 stars out of 5
Murray , Utah
Dec 27, 2019
Pros: Blade Sharpness, Handle Material, Overall Quality, Pocket Clip, Ease of Opening, Lock Type, Handle Feel, Weight, Lock Ease of Use, Blade Material
Cons: Blade Sharpness, None
Very cool knife
Read all 58 Reviews »
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