SOG Pentagon MK3 Tactical Knife – Review

A good self defense knife and a pistol and you're in good shape to defend yourself. If you need your weapons concealed a little Bers Thunder .380 and a SOG If you're in the market for a self defense knife check out the SOG Pentagon MK3 fits the bill.
A good self-defense knife and a pistol and you’re in good shape to defend yourself. If you need your weapons concealed a little Bers Thunder .380 and a SOG If you’re in the market for a self-defense knife check out the SOG Pentagon MK3 fits the bill.

U.S.A.-( The SOG Pentagon MK3 is a tactical knife. It has a wide spear point 3.66” blade which is tipped with a slight back edge and is cryogenically heat-treated CTS XHP stainless steel. This knife is designed for self-defense.

SOG Pentagon MK3 Tactical Knife

When you employ the knife, you will feel like that you have a firm grip on it due to the thumb grooves on the top of the G10 handle, the grooves on the hilt of the handle under your palm, and the grooves on the bottom of the handle under your middle finger. The finger groove further enhances your grip and I think the grooves on the flipper also helps hold your pointer finger in place if it slips forward. I do wish that the top of the spine on the hilt was flat and had thumb grooves for 1”. But I guess with the thumb grooves and the thumb studs that is sufficient.

It has a reversible pocket clip that allows you to clip the SOG Pentagon MK3 onto your pocket or a strap on your backpack. Due to how that the clip is positioned the knife sets rather low and inconspicuously in your pocket but is readily accessible.

I like the locking SOG XR Lock system. It has a sliding ambidextrous lock. Push it back to unlock and close the blade. SOG claims to have the ultimate built-in blade locking security when open and is able to withstand up to 1,500 pounds of force. They say that it is strong enough to hold a Toyota (Not that I know anyone capable of lifting a Toyota with the tip of their knife).

Fifty years ago, to open our folders one-handed we had to slightly open the tip of the knife and then hang it on the seam on the leg of our Wranglers and flip it open. That was the closest thing to a one-handed opening folder that we ever heard of. Opening the SOG Pentagon MK3 one-handed is easy and they afford you three options in which to perform a one-hand opening.

  1. Thumb studs
  2. Flipper on the bottom hilt side of the blade. There are finger groves on it which also further aids in the opening.
  3. Or, you can slide the lock back and with the flip of the wrist and the blink of an eye it is open.

Of the above three options, I favor the flipper.

I’m not a tactical type of guy. I’m an outdoorsman and fish, hunt, backpack etc. By the same token, we all live in a fallen world so unfortunately sometimes you have to protect your loved ones. I’m not up on all of the current knife laws. Heck, here in Idaho there used to be a knife booth in the mall that sold switch blades so we can kinda carry whatever we want here but I faintly remember reading that in some states knives sharpened on both edges were illegal and classified as stilettos. The top edge on the SOG Pentagon MK3 has almost an edge. I’m sure one of you little scalawags out there will buy one and put a real edge on it. (And put a pic of it on Fakebook and get reported and go to FB jail). And with that we will close down this Product Review.

The SOG Pentagon MK3 is offered in black or OD Green and the MSRP is $174.95 and as is usual, we will close with the specs.

  • OVERALL LENGTH – 8.38 in
  • CLOSED LENGTH – 4.77 in
  • BLADE LENGTH – 3.6 in
  • WEIGHT – 4.9 oz
  • BLADE THICKNESS – 0.12 in
  • OPENING MECHANISM – XR, Thumb stud, Kick
  • FINISH – Black Titanium Nitride
  • BLADE SHAPE – Spear Point
  • EDGE TYPE – Straight

Tom ClaycombAbout Tom Claycomb

Tom Claycomb has been an avid hunter/fisherman throughout his life as well as an outdoor writer with outdoor columns in the magazine Hunt Alaska, Bass Pro Shops,, and freelances for numerous magazines and newspapers. “To properly skin your animal, you will need a sharp knife. I have an e-article on Amazon Kindle titled Knife Sharpening #ad for $.99 if you’re having trouble.”

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1 year ago

Michigan is one of the states where a stiletto is a no no. Also, a dagger, dirk, ice pick, etc. Brass knuckles, police baton, sap, taser, unless you have a CCW permit, all illegal to carry. I have carried a knife since I was age 9. In school, back then, I carried it in my pocket, and was never questioned about it. I was born in 1960, if that tells you the time frame. I didn’t use it everyday, but as most of us know, when you carry a knife, you find that you use it often. I now have… Read more »

1 year ago

Some of their knives are produced in the U.S.A. This isn’t one of them, as noted above. Still, it isn’t made in the PRC so that is a plus. I was looking at this a few days ago after receiving their advert of the sale. Still on the fence about it as I am looking for U.S. product.
Curious about the dowel(?) that runs down the center of the blade. Stiffener?
Don’t know what knife you used to carry but back when I had stronger wrists, I could flip my Buck 110 open with a snap of one hand.

1 year ago
Reply to  jukk0u

Ive had Taiwanese steel from SOG before it does just fine. Most of the stuff out of there under a “known” name these days is solid. I have just grown accustomed to a nice solid 1095.

Dave in Fairfax
Dave in Fairfax(@grammar)
1 year ago
Reply to  Random71

1095 is good steel, You just have to be willing to guard against rust as it’s not SS.
W-2, 5160 and the oil hardening steels O-1 and O-2 make good blades as well, just quench the W-2 in oil not water to avoid brittleness. They’re all easy to work on a hand forge and both temper and anneal easily. Try it, you’ll like it.

1 year ago

Oh I know, Ive had an OKC in 1095 for 15 years, not a dot of rust on it. Just takes a minute and drop or two of oil.
The options out there are plentiful and normally solid, I’ve tried many. If I had a forge set up then totally would be interested in the other options.
In this day and age we are spoiled with choices in steel and I am open to try them, I just happened to settle on 1095 for now.

Dave in Fairfax
Dave in Fairfax(@grammar)
1 year ago
Reply to  jukk0u

That “dowel” down the center looks like a fuller to me. If it is, it’s for stiffening, just like the channels in an I-beam.