By Brandon Moss
SOG doesn’t bury the lead on the Pentagon FX. Their own description calls it a knife built for the modern day warfighter. A professional use fixed blade designed for military and law enforcement. That’s a specific claim, and the Pentagon FX Elite backs it up with a design, material selection, and construction standard that earns the classification.
SOG brought in Todd Begg, a knife maker for over 40 years, who’s been on the front end of tactical knife making for a few decades, to design the Pentagon FX Elite. The knife is built in the United States from 100% American-sourced materials. SOG has been building up the Pentagon series and the Elite sits at the pinnacle of it.
Pentagon FX Elite’s Purpose
SOG categorizes this under Professional Use. The 5.75-inch double-edged dagger profile was chosen because a dagger does one thing better than any other blade geometry, it penetrates. It does so with both a forward and reverse grip, symmetrically. SOG designed it to perform under the conditions that professionals in demanding roles actually encounter. That intent shapes every decision made on this knife, from the steel selection to the sheath.
The Pentagon FX Elite exists for a specific reason entirely, protection.
SOG built the Pentagon FX Elite around what they call mission specific setup. The Kydex sheath isn’t a static piece of hardware, it’s a carry platform. Belt, pack strap, MOLLE, whatever situation you need, the attachment system is designed to be configured for the actual deployment scenario rather than defaulting to one carry position. Adjustable sheath retention, secondary retention, mounting angle, and mounting method are all field-adjustable without tools, making it diverse on the go.
That modularity reflects the professional use intent. A knife going on a plate carrier for a military operator is configured differently than the same knife riding on a belt for law enforcement or personal protection. The Pentagon FX Elite accommodates all setups without requiring the user to source additional hardware.
The Right Steel
CPM S35VN is the right call for the Pentagon FX Elite, and the reasoning is worth understanding. Where a backcountry fixed blade like the Hidaka FX runs CPM-3V for maximum toughness under hard field use, the Pentagon FX Elite’s professional context shifts the priority. S35VN is a stainless steel that handles the wet, variable, and often coastal or humid conditions that military and law enforcement deployment frequently involves, without demanding the maintenance discipline that a true tool steel requires. Edge retention is excellent, the steel sharpens cleanly without the difficulty that harder, tougher steels present, and the cryo treatment pushes performance further across the board.
The 4mm blade thickness is stout without being excessive. The flat black PVD coating handles glare and adds corrosion resistance without obscuring the grind line or adding meaningfully to the profile. At 58-61 HRC, it’s hard enough to hold a serious edge under hard use without becoming brittle at the tip, a meaningful detail on a double-edged dagger where the tip takes more stress than on a conventional blade geometry.
SOG is explicit about this: the Pentagon FX Elite is designed and manufactured in the United States, from 100% American sourced materials. At a price point where imported knives with similar specs are common, domestic manufacture at this fit and finish standard is not a given. It shows in the consistency of the grind, the quality of the Micarta handle scales, and the overall execution of a knife that needs to perform reliably under conditions where failure is not an acceptable outcome.
Linen Micarta over a full tang construction gives you a handle that grips in any condition, wet, cold, gloved without synthetic rubberized materials that can harden or degrade in extreme cold. Full tang eliminates the handle to blade junction as a structural weak point. On a knife in this category, that’s not a feature to be listed, it’s a baseline requirement, and SOG meets it.
Who It’s For
The Pentagon FX Elite is SOG’s top-tier expression of a purpose-built professional fixed blade. Military personnel, law enforcement officers, and serious tactical users who need a double-edged fixed blade that performs under hard use in variable deployment conditions will find it earns its price and its classification.
Collectors who appreciate American-made, designer, collaborated fixed blades at the top of a respected production lineup will find it equally compelling. It’s for the person who wants a knife that looks good and performs even better, when the time is needed.
Pros: Professional use designation backed by purpose-built dagger geometry; CPM S35VN cryo treated at 58-61 HRC; Todd Begg design collaboration; full tang linen Micarta construction; mission configurable Kydex sheath with multiple carry setups; made in the USA from American-sourced materials; lifetime warranty.
Cons: Double-edged dagger geometry limits utility for general field tasks; significant price point; purpose-specific.
Cost: MSRP of $449.95.
