Product Description
The Manbug Lightweight MFPK390 is a uniquely practical small folder that Spyderco says feels at home in larger hands while still fitting inconspicuously in a pocket or on a keychain. This version pairs a full-flat-ground K390 MICROCLEAN blade with blue FRN, the signature color of Spyderco's K390 family, at just 0.7 ounces.
K390 MICROCLEAN is a powder metallurgy cold work tool steel from Böhler-Uddeholm, developed for the wear resistance and compressive strength needed in industrial cutting, blanking, and punching. In a knife this small, that means an edge that keeps working through packages, tape, and daily chores between sharpenings. The thin 0.098" leaf-shaped blade is full-flat ground for clean slicing. The trade-off is care: it isn't stainless, so it needs to be kept clean and dry.
- Blade: 1.96" K390 MICROCLEAN leaf-shaped blade with a 1.70" PlainEdge, full-flat grind, satin finish, 0.098" thick.
- Handle: Blue FRN with Spyderco's Bi-Directional Texture and a lanyard hole; 2.50" closed, 0.7 oz.
- Deployment + Lock: Spyderco Trademark Round Hole for one-handed opening; a Back Lock holds the blade open and releases by pressing the lock bar on the spine.
- Carry: No pocket clip; carries on a keychain or loose in a pocket; 4.46" overall.
Ideal for: EDC carriers who want a capable keychain knife; steel enthusiasts collecting Spyderco's K390 family; and anyone who wants a small blade under 2.5 inches that still fills the hand.
Knife laws vary by location. Check your local laws before you buy or carry.
Care note: K390 MICROCLEAN is a tool steel, not a stainless steel. It may patina or rust, so wipe it clean and dry after use and keep a light coat of oil on the blade.
The Spyderco Manbug Lightweight in K390 MICROCLEAN with blue FRN (MFPK390) ships same or next business day from Columbia, Louisiana. Knifeworks is an authorized Spyderco dealer.
Spyderco Manbug Lightweight K390: Frequently Asked Questions
Answers to the most common questions about the Spyderco Manbug Lightweight (MFPK390).
What lock does the Spyderco Manbug Lightweight MFPK390 use?＋
The Manbug Lightweight uses a Back Lock. When the blade opens, a spring-loaded lock bar in the spine of the handle drops into a notch in the blade tang and holds it securely. To close, press the exposed section of the lock bar on the back of the handle and fold the blade, keeping your fingers clear of the edge.
How do you carry the Manbug?＋
The Manbug has no pocket clip. At 0.7 ounces and 2.50 inches closed, it is small enough to carry on a keychain through its lanyard hole or loose in a pocket. Spyderco designed it to feel at home in larger hands despite its small size.
What is K390 MICROCLEAN steel?＋
K390 MICROCLEAN is a powder metallurgy cold work tool steel from Böhler-Uddeholm, developed for the wear resistance and compressive strength needed in industrial cutting, blanking, and punching. Its fine, uniform microstructure gives it long edge life in a knife blade. Spyderco marks its K390 knives with a blue handle color.
How do I care for a K390 blade?＋
K390 MICROCLEAN is not a stainless steel, so it may develop a patina or rust if left wet or dirty. Wipe the blade clean and dry after use, especially after cutting food or handling it with sweaty hands, and keep a light coat of oil on it. Because it is so wear resistant, diamond or CBN abrasives work best for sharpening.
What comes with the Manbug Lightweight MFPK390?＋
The MFPK390 ships as the knife alone, with no pocket clip, sheath, or keyring included. Packaging and included items are set by Spyderco and are subject to change.
Where is the Manbug Lightweight MFPK390 made, and what warranty covers it?＋
This Manbug Lightweight is made in Japan. Spyderco warrants that its genuine products are free from defects in material and workmanship for the life of the product. The warranty does not cover loss, theft, accidents, abuse, misuse, improper sharpening, normal wear and tear, or alterations. Shipping to and from Spyderco is the owner's responsibility. Contact Spyderco directly and include the Spyderco Warranty & Repair Form with any return. Knifeworks does not warranty this product independently.
K390 MICROCLEAN · KEYCHAIN SIZE · 0.7 OZ
A Keychain Knife in K390
A 0.7 oz Back Lock folder with a 1.96-inch K390 blade, sized for a keychain or pocket. Questions? Our team carries these knives daily. We ship same or next business day from Columbia, Louisiana.
Call 888-225-9775
Warranty Information
Spyderco Warranty: Spyderco warrants that its genuine products are free from defects in material and workmanship for the life of the product. The warranty does not cover loss, theft, accidents, abuse, misuse, improper handling, alterations, neglect, improper sharpening, normal wear and tear, aftermarket or modified parts, or repairs by services not authorized by Spyderco, and broken, lost, or bent metal clips are typically not covered. If Spyderco finds a defect, it will repair or exchange the knife with the same, a similar, or an equal-value model. Shipping to and from Spyderco is the owner's responsibility. Contact Spyderco directly and include the Spyderco Warranty & Repair Form with any return. Knifeworks does not warranty this product independently.Specifications
| Product Type | Folding Knife | |
| Brand | Spyderco | |
| Product Name | Manbug Lightweight | |
| Model # | MFPK390 | |
| Overall Length | 4.46 in | |
| Closed Length | 2.50 in | |
| Blade Length | 1.96 in | |
| Blade Thickness | 0.098 in | |
| Blade Material | Böhler K390 MICROCLEAN | |
| Blade Style | Leaf Shape | |
| Blade Edge | Plain | |
| Blade Grind | Flat | |
| Handle Material | FRN | |
| Handle Finish | Bi-Directional Texture | |
| Lock Type | Back Lock | |
| Clip Position | None (keychain / pocket carry) | |
| Weight (oz) | 0.7 | |
| Origin | Japan | |
| Blade Range | 1-1.99 | |
| Edge Length | 1.70 in | |
| Blade Finish | Satin | |
| Handle Color | Blue |
