The Back Door: Used – Microtech LUDT 3.5" Auto Folder, M390MK, Purple Aluminum, Factory Serviced, Box Included

This item is listed in The Back Door.

This knife is listed in The Back Door. It was acquired as a local trade described as like new, but arrived in used and worn condition. The previous owner sent it directly to Microtech for repair and sharpening. It has been returned fully serviced by the manufacturer and is now in excellent working condition. Original box is included along with the Microtech warranty and repair paperwork from the service.

Microtech serviced. Purple aluminum. M390MK auto.

The Microtech LUDT is one of the most iconic side-opening automatic knives ever produced, tracing its lineage directly back to the original UDT — a knife built for automatic deployment underwater for Special Operations use. This Purple Gen III example has been through a factory service at Microtech, meaning it was inspected, repaired, and sharpened by the people who built it. The 3.5" M390MK drop point blade now carries a fresh factory edge and the mechanism has been confirmed functional by Microtech's own shop. 24 silica carbide bearings in the pivot, milled titanium backspacer, Torx hardware, and purple anodized 6061-T6 aluminum handle.

M390MK is Microtech's proprietary variant of Bohler M390, with improved edge retention over the standard alloy. The button lock secures the blade both open and closed. Tip-up carry, lanyard hole, and a deployment that has been described as one of the most satisfying side-openers in production.

Note from Lone Star Knife & Supply: Getting a Microtech that has been factory serviced is not the worst thing in the world. The knife that comes back from Microtech's shop is sharp, functional, and verified. The paperwork is in the box. Purple is one of the better LUDT colorways. This is a solid Back Door pickup.

Why This LUDT Stands Out

• 3.5" M390MK Drop Point Blade, Microtech's proprietary high-retention steel
• Factory serviced by Microtech prior to sale, returned sharp and fully functional
• Warranty and repair paperwork from Microtech service included in box
• 24 Silica Carbide Bearings in pivot for ultra-smooth deployment
• Purple Anodized 6061-T6 Aluminum Handle
• Button Lock, secures blade both open and closed
• Made in the USA (Asheville, North Carolina)

Specifications

• Brand: Microtech Knives
• Model: LUDT Gen III
• Blade Length: 3.5"
• Overall Length: 8.0"
• Blade Steel: M390MK
• Blade Style: Drop Point
• Handle Material: 6061-T6 Aluminum
• Handle Color: Purple Anodized
• Lock Type: Button Lock
• Action: Automatic Side-Opening
• Pocket Clip: Tip-Up
• Condition: Used. Factory serviced by Microtech.
• Includes: Original box, Microtech warranty and repair paperwork
• Weight: 3.6 oz
• Country of Origin: Made in USA (Asheville, North Carolina)

Why You'll Want It

A LUDT that has been through Microtech's own service facility is a known quantity. It is sharp, it is functional, and the paperwork that says so is in the box. Purple with M390MK at a Back Door price is exactly the kind of deal this section was built for.

About Microtech Knives

Microtech Knives has manufactured every knife in their lineup in Asheville, North Carolina since 1994. The LUDT traces its lineage to the original UDT, Microtech's first production knife. Every Microtech is backed by a lifetime warranty.