Quantum

Overview

The Quantum is the newest of the workshop’s frame lock designs: an upswept, Persian-style 95 mm blade on a handle slimmer than the F95’s, with milling patterns designed for it, a suspended backspacer and a clip on a hidden screw. It began as a Sergey Shirogorov custom, took Best Tactical Knife at Blade Show Atlanta in 2019, went through the Custom Division that fall, and reached serial production on 21 March 2020 as the Quantum 3M. On a listing the first question is which tier: the serial Quantum in its two generations, an Ursus working knife, a Custom Division run, a Sprint Run, or a dealer edition, because the same shape sells at every one of them.

The blade is a full flat grind with minimal jimping, 3.5 mm on the Ursus knives, in M390 on the serial line, Cromax PM on the Quantum Ursus knives from December 2021 and Elmax on the Q95 Ursus. The frame is 3D-milled 6Al-4V titanium with a steel insert on the lock face, on MRBS, with the Quantum Ursus NL on a single row of balls (SRBS). The serial 3M weighs 135 g and the Gen 2 122 g. Factory specifications for every model in the line are on the Quantum record.

At a glance:

• Designer: Sergey Shirogorov
• First release: Custom Division fall 2019; serial 21 March 2020
• Generations: two on the serial line, the 3M of March 2020 and the Gen 2 of 18 September 2021
• Related lines: the Ursus working line on this platform, from the Quantum Ursus NL of December 2021 to the Q95 Ursus; the Mini Quantum (85 mm) and MidiQ (90 mm) in the Custom Division; the F95 (the drop point the workshop is built on)

Variants comparison

Every model in the line: kind, release, blade, steel, bearing system, lock, handle, weight and run size.

Production history

• 2019: Sergey Shirogorov’s custom Quantum takes Best Tactical Knife at Blade Show Atlanta; the Quantum CD is announced on 17 June 2019 beside a Damasteel Sprint Run of thirty, and Custom Division production runs from the fall.
• 21 March 2020: Quantum 3M, the first serial generation, in the Three Bears category, in M390 at 135 g.
• 18 September 2021: Quantum Gen.2, the second serial generation, 122 g.
• 9 December 2021: Quantum Ursus NL, titanium with inlays in G10, Micarta, carbon fiber and other materials, in Cromax PM on SRBS, the first knife of the Ursus line.
• 6 April 2022: Quantum Ursus, with G10 or wood inlays in the titanium, Cromax PM on MRBS, 122 g.
• February 2023: Quantium Ursus, a G10 handle in Cromax PM, 110 g.
• 22 July 2023: Quantum Ursus Lefty, titanium in Cromax PM, 118 g.
• 2024: Quantum Ti BB “Blue Beast”, blue anodized titanium, 100 pieces; MidiQ CD, 100 pieces, after Sergey’s custom MidiQ took Best M.A.C.K. at Blade Show Atlanta.
• June 2025: Q95 Ursus, Micarta over titanium liners on a liner lock, in Elmax, with hex-bit hardware; December 2025: Q95 NY26 in white Micarta; May 2026: Q95 Ursus Ti, all titanium on a frame lock.
• Custom Division runs: Quantum CD (the Blue CD, 50 pieces, S90V), Quantum Bronze CD (50, Vanadis 10), Mini Quantum CD (50, 85 mm in M398), MidiQ CD (100, 90 mm in MagnaCut) with a MidiQ Damascus of 25.

Variants

Quantum 3M and Quantum Gen.2

The serial Quantum: the upswept 95 mm blade in M390, a 128 to 130 mm handle in 3D-milled titanium with the model’s own milling patterns, the suspended backspacer and the hidden clip screw, on MRBS. The 3M of March 2020 weighs 135 g and the Gen 2 of September 2021 122 g; a factory notice of 31 March 2022 dropped the 3M suffix from model names.

Quantum Ursus

The working version, on sale since April 2022: the same blade in Cromax PM, with G10 or wood inlays set into the titanium scales for grip and cost, 122 g, 129 mm handle, 224 mm overall, on MRBS.

Quantum Ursus NL

The first Ursus, of December 2021: titanium scales with inlays in G10, Micarta, carbon fiber and other materials, Cromax PM (the steel’s first use on the line), 129 mm handle, 125 g, on SRBS. The NL is the one serial-tier Quantum on a single row of balls, which matters on a listing that claims MRBS.

Quantium Ursus and Ursus Lefty

The Quantium Ursus of February 2023 puts the Ursus blade in a G10 handle at 110 g. The Quantum Ursus Lefty of July 2023 is the mirrored build in titanium and Cromax PM at 118 g.

Q95 Ursus

The 95 mm liner lock of the Ursus line, from June 2025: Micarta over titanium liners, an Elmax blade, and hex-bit hardware in place of the workshop’s slotted screws. The Q95 NY26 of December 2025 wears white Micarta and the Q95 Ursus Ti of May 2026 is all titanium on a frame lock. With the F95 Ursus it is the first step on the ladder in Choosing your first Shirogorov; the Q95 record has its rows.

Mini Quantum CD and MidiQ CD

Custom Division pieces that scale the Quantum’s blade down. The Mini Quantum CD carries an 85 mm blade in M398 with complex anodizing on SRRBS, in a run of 50, and took Best Investor/Collector Knife in the factory competition at Blade Show Atlanta in 2023. The MidiQ CD of 2024 is a frame lock with a 90 mm MagnaCut blade at 3.5 mm, an anodized titanium handle, the RPC rotating pocket clip and an SRRBS pivot, in a run of 100. A MidiQ Damascus of 25 is among its editions, and the 2024 Best M.A.C.K. went to Sergey’s custom MidiQ, not to the CD piece. The Mini Quantum SR, a Sprint Run, carries a rotating clip that separates it from the fixed-clip Mini Quantum CD. The tier ladder places both lines.

Quantum Ti BB “Blue Beast”

A 2024 edition of 100 numbered pieces in blue anodized titanium.

Custom Division Quantums and the Sprint Runs

The full-size Custom Division runs are the Quantum CD, the Blue CD, 50 pieces in S90V with complex anodized titanium, and the Quantum Bronze CD, 50 pieces in Vanadis 10 with bronze and carbon fiber, both on SRRBS with hand finishing and tighter tolerances. The Quantum Sprint Run is thirty numbered pieces in Damasteel on single-row rollers, with zirconium hardware. Dealer listings have filed them under a Custom Division heading, and a listing that reads “Sprint Run Custom Division” is describing one knife with two labels. The E-Knives Quantum Ursus edition of 30 is a dealer exclusive on the serial tier, whatever the listing calls it. The Custom Division FAQ and the Sprint Run register separate them; the steels page has the factory’s hardness bands.

Authentication

What to check on a Quantum, in the order a buyer can check it.

The box and the certificate carry the serial. Most Quantums have no engraved serial; the original box and the certificate of authenticity (COA) are the record, and the certificate names the variant, the steel and any edition. A Custom Division Quantum also carries its markings inside, on the scales and/or the backspacer, with a CD mark beside the bear head. A Sprint Run is numbered NN/30 on the box and the COA, NN/3 for the Damasteel Quantum.

The upswept blade, the suspended backspacer and the hidden clip screw. Those three came to the serial lines with the Quantum; a drop point on this handle is not a Quantum, and the clip screw doesn’t show.

The pivot tells the tier. A serial Quantum and a Quantum Ursus run MRBS; the Quantum Ursus NL runs SRBS. A Custom Division or Sprint Run Quantum runs SRRBS, a single row of loose rollers per side, so the bearings don’t separate those two tiers; the markings and the certificate do. A duck foot pivot belongs only to Sergey’s full customs.

Slotted screws, except on the Q95. A serial or Custom Division Quantum takes the workshop’s slotted hardware; the Q95 Ursus takes hex bits. Torx screws mean someone has replaced the hardware, or the knife isn’t what it says.

The scales name the tier. Titanium with the model’s milling is the serial Quantum; a mirrored titanium build is the Ursus Lefty. Inlays in titanium are the Ursus or the Ursus NL, with the certificate naming which, and all titanium on a frame lock is the Q95 Ursus Ti. A G10 handle is the Quantium. Micarta over liners is the Q95. Blue anodized titanium with a number is the Ti BB. Complex anodizing or bronze is a Custom Division run; damascus is a Custom Division edition (the MidiQ Damascus) or a Sprint Run, and the certificate says which.

The weight confirms the generation. 135 g on the 3M, 122 g on the Gen 2 and the Ursus, 125 g on the Ursus NL, 118 g on the Ursus Lefty, 110 g on the Quantium. A knife well off its figure needs an explanation from the seller.

The per-tier checklist, the photographs to ask for and the remote-buying rules are on the authentication guide.

Telling the generations apart

Two serial generations, and the box and certificate name them. The 3M of March 2020 weighs 135 g and the Gen 2 of September 2021 122 g; the 3M name belongs to the Three Bears category, which the factory retired from model names in March 2022. The Ursus knives are not generations but a line, told apart by their scales and their dated releases above.

Pricing and collecting

Prices are in the price record; the questions a buyer asks before paying are on the Buying FAQ. On a Quantum listing the tier is the first question; the early 3M, the Ti BB and the Custom Division runs are the ones with their own trading histories.

Questions answered: Models FAQ.