Benchmade 5400SBK Serum AXIS Dual-Action AUTO 3.47" Black Combo Blade, G10 Handles

Part #: BM5400SBK | Benchmade Knives


This product is no longer available
BM5400SBK: 5400SBK Serum | Benchmade Design
The 5400 Serum knife features the revolutionary AXIS dual-action mechanism. One of the strongest, most versatile automatic mechanisms on the market for nearly 20 years has evolved. The AXIS Dual-Action automatic or manual opening combines the superior ambidextrous function of the manual AXIS with a covert automatic action triggered by pulling the AXIS bar down further. No matter the job, the AXIS dual-action has you covered.

Featuring 154CM stainless steel, this is a proven steel for tactical applications. Its well-balanced characteristics promote performance in the most demanding situations asked of in a tactical folder. 154CM is a martensitic stainless steel with molybdenum content. The molybdenum is what gives 154CM good toughness which is based off a combination of ductility and strength. In addition, 154CM has good hardness and corrosion resistance qualities.

Operating the 5400 Serum:

The Benchmade 5400 Serum™ features the AXIS Dual-Action mechanism which can function either as a AXIS manual or as an AXIS auto. To operate the knife as an automatic, pull the AXIS bar back to the furthest position to actuate the automatic opening function.

The AXIX Dual-Action mechanism has a "dry-fire" safety that initiates when the blade is not fully closed. This features aids in the safe operation of the knife and prevents the automatic function from firing when not intended to be used.

About the "Dry-fire" Safety:

The AXIS Dual-Action mechanism has a secondary safety system built in to eliminate a "dry-fire." A dry-fire is when a torsion or leaf kicker spring is released without adequate resistance. The uncontrolled release of energy is unstable and can cause the spring to fracture. In addition the potential of a catastrophic failure, a dry-fire can greatly reduce the life of the spring and create a dangerous situation for the user with the spring unwinding and colliding into the blade. This situation would result in the knife opening in an unpredictable manner.

The dry-fire mechanism locks the automatic mode out by blocking the lock stud from going back far enough to release the spring bushing.

The dry-fire safety is engaged whenever the blade is not in the closed position. The AXIS® lock bar provides the closed position detent. Pulling back the AXIS bar will release the detent and can allow the blade to open partially if the knife is held horizontally. In this case the dry-fire safety will engage. To actuate auto mode, the blade must remain in the handle until the bushing is released and the spring uncoils.
  • AXIS dual-action mechanism
  • Modified drop-point blade
  • 154CM stainless steel blade (58-60HRC)
  • Black machined G10 handle scales with full stainless steel liners
  • Reversible tip-up pocket clip
  • Blade Length: 3.47" (8.81 cm)
  • Blade Thickness: 0.120" (3.05 mm)
  • Open: 8.09" (20.55 cm)
  • Closed: 4.70" (11.94 cm)
  • Weight: 4.63 oz. (131.26 g)
  • Handle Thickness: 0.58" (14.63 mm)
  • Made in USA
Pocket Clip
Pocket Clip
Includes a pocket clip for easy accessibility and a more secure carry.
Made in USA
Made in USA
This product is USA born and raised.
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.


Subscribe to our Newsletter for exclusive offers!