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This article is about the light STO-series BattleMech. For the apocryphal ultralight STD-series BattleMech, see Stiletto (StarDrive).
Production information
Manufacturer Coventry Metal Works[1]
Production Year 3061[2]
Model STO-4A[1]
Class Light
Cost 5,167,125 C-bills[2]
Technical specifications
'Mech type Inner Sphere BattleMech
Mass 35 tons
Chassis MatherTech 750 Endo Steel[1]
Armor Lexington Ltd. High Grade ferro-fibrous[1]
Engine VOX 280[1]
Communications System Cyclops 14[1]
Speed 129.6[1] km/h
BV (1.0) 746[3]
BV (2.0) 859[1][2][4]


The Stiletto was engineered in a similar vein as the Black Hawk-KU or the Rakshasa, using examples of Fire Falcon OmniMechs salvaged from the battlefield immediately following the Battle of Coventry. The Stiletto has an identical speed profile as the Fire Falcon with a VOX 280 Light Engine giving it a top speed of 129.6 km/h. The Stiletto also has an almost identical visual profile to the 'Mech which it tries to emulate, and is built on a lightweight MatherTech 750 Endo Steel chassis that supports six tons of Lexington Ltd. High Grade ferro-fibrous with CASE to protect against an ammunition explosion. The Stiletto also has a Guardian ECM Suite which protects the 'Mech from advanced electronic warfare equipment.[1]

Weapons and Equipment[edit]

The Stiletto is armed for both long and short range combat. For close combat, the Stiletto has two Coventry T4H Streak SRM-2 launchers. For long range combat, the Stiletto has a single Coventry Five-Tube LRM-5 launcher that makes the Stiletto capable of both direct and indirect missile support. The weapons payload of the Stiletto has received some criticism as the 'Mech is completely dependent on ammunition based missile weapons.[1]


  • STO-4B 
    Designed in 3063[5] as a response to criticism over the 4A variant's ammunition dependence, the 4B removes all of the missile weapons and replaces them with a single ER Large Laser and two ER Medium Lasers. A Flamer rounds out the arsenal on the 4B, making the 'Mech highly effective against unarmored infantry. BV (1.0) = 936[3] BV (2.0) = 1,164[6][5]
  • STO-4C 
    This variant developed in 3076[7] replaces the standard weaponry with a pair of ER Medium Lasers and an MML-5 missile launcher. It also adds additional armor. BV (2.0) = 941[8][7]
  • STO-6S 
    This Stiletto is the production variant of the STO-6X introduced in 3083. The weapons, armor, and Bloodhound Active Probe all remain unchanged, but the engine Supercharger has been exchanged for a Guardian ECM Suite. This allows the Stiletto to interfere with the electronic systems commonly used by the Word of Blake. BV (2.0) = 1,171[11][12]

Apocryphal Content Starts

The information after this notice comes from apocryphal sources; the canonicity of such information is uncertain.
Please view the reference page for information regarding their canonicity.

  • FRF-W 
    This variant carries six tons of armor and more weapons. It is armed with one Large Pulse Laser, two LRM Racks, and an Intermediate Sensor.
  • FRF-J 
    The FRF-J has the same armament as the FRF-A and six tons of armor. Its jump jets allow it to jump up to one-hundred thirty-four meters.

Apocryphal Content Ends

Related BattleMechs[edit]

Design Quirks[edit]

The STO-4A Stiletto has the following Design Quirks:[13]

The STO-6S Stiletto has the following Design Quirks:[11]




  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 Technical Readout: 3067, pp. 56–57: "STO-4A Stiletto"
  2. 2.0 2.1 2.2 MUL online entry for the Stiletto
  3. 3.0 3.1 Combat Operations, p. 132: "Force Faction Tables"
  4. Record Sheets: 3067 Unabridged, p. 85
  5. 5.0 5.1 MUL online entry for the Stiletto STO-4B variant
  6. Record Sheets: 3067 Unabridged, p. 86
  7. 7.0 7.1 MUL online entry for the Stiletto STO-4C variant
  8. Record Sheets: 3067 Unabridged, p. 87
  9. Experimental Technical Readout: Steiner, p. 3: "STO-6X Stiletto"
  10. MUL online entry for the Stiletto STO-6X variant
  11. 11.0 11.1 Technical Readout: Prototypes, p. 103: "STO-6S Stiletto"
  12. MUL online entry for the Stiletto STO-6S variant
  13. BattleMech Manual, p. 95: BattleMech Quirk Table - Stiletto Entry.