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Msv Focus HEX Ultra Black 125

Msv Focus HEX Ultra Black 125  

Test published on 19/03/2018
Msv Focus HEX Ultra Black 125 is a monofilament with hexagonal shape and composition based on copolyester.
The average static stiffness is 0.92 kg/mm.
  Tension holding   Spin   Resilience peak

General info

Typology Monofilament
Shape Hexagonal
Composition Copolyester
Available colors White, Black
Available gauges 110, 115, 120, 125, 130

Technical data

Tension range 17 - 22 kg
Playing life 8 - 12 hrs
Resilience range 14 - 18 kg
Prestretch (recommended) No  
Progressive plasticization No  

Characteristics

Power 85 / 100

+4 average-related
Resilience peak 90 / 100

+13 average-related
Elasticity 60 / 100

+6 average-related
Spin 95 / 100

+5 average-related
Control 85 / 100

-6 average-related
Tension holding 100 / 100

+23 average-related
Stability 70 / 100

+5 average-related
Comfort 65 / 100

-3 average-related

Stiffness
Tough

Static stiffness 10-15kg 1.35 kg/mm
0.03 kg/mm average-related
Static stiffness 15-20kg 0.95 kg/mm
0.07 kg/mm average-related
Static stiffness 20-25kg 0.85 kg/mm
0.05 kg/mm average-related
Static stiffness 25-30kg 0.95 kg/mm
0.07 kg/mm average-related
Static stiffness 30-35kg 1 kg/mm
0.13 kg/mm average-related
Average static stiffness 15-30kg 0.92 kg/mm
0.02 kg/mm average-related
Dynamic stiffness 230 g/mm
2.14 g/mm average-related
Dynamic stiffness (string selector test simulator)225 lbs/inch
Equal to average
Average elengation 5-35kg35.33 mm
0.75 mm average-related

Strings with similar behaviour

Similar strings (Power)

Similar strings (Resilience peak)

Similar strings (Elasticity)

Similar strings (Spin)

Similar strings (Control)

Similar strings (Tension holding)

Similar strings (Stability)

Similar strings (Comfort)

Progressive plasticization

Progressive plasticization is a phenomenon that affects tennis strings over time, especially monofilament types. As the strings are used, they gradually lose elasticity, snapback, and responsiveness — negatively impacting racquet performance on the court.

🎾 What is progressive plasticization?

When hitting the ball, strings deform to absorb energy. In materials like polyester, part of that deformation becomes permanent. This gradual accumulation is known as progressive plasticization — where strings become stiffer, less elastic, and less comfortable with use.

📏 String types and susceptibility

String TypePlasticization Tendency
Monofilament polyester🔴 High – loses tension and snapback quickly
Multifilament or natural gut🟢 Low – maintains elasticity and feel longer
Hybrid (mono + multi)🟡 Medium – good balance between durability and resilience

⚙️ Effects on play

  • Tension loss: strings stretch and lose their original tension, reducing control.
  • Stiffness and discomfort: more vibrations are transferred to the arm, increasing fatigue or risk of injury.
  • Reduced snapback: the ball spends less time on the stringbed, lowering spin and consistency.
  • “Dead string” feel: shots feel dull, with less power and feedback.

🎯 In practice

If you use polyester strings, it’s crucial to restring regularly — even before they break — to avoid plasticization effects. Players seeking more comfort or consistency can opt for multifilaments or hybrid setups. Be mindful that heat and long periods of inactivity can also accelerate the degradation of string performance.

Prestretch

Prestretching tennis strings is a technique used to reduce tension loss and improve stringbed stability. It involves stretching the string manually or mechanically before or during the stringing process. This is especially useful for polyester or stiff monofilament strings that tend to lose tension quickly.

🎾 What is prestretching?

Prestretching means applying extra tension to the string before it's installed in the racquet. This can be done manually by pulling the string and holding it for a few seconds, or automatically through a stringing machine with a prestretch function. The goal is to minimize the natural elongation that occurs during play, ensuring more consistent performance and reducing the break-in period.

📏 Types of prestretching

Prestretch MethodDescription
Manual prestretchThe string is pulled by hand before installation and held under tension for 5–10 seconds to reduce initial elasticity.
Automatic prestretchSome electronic stringing machines apply about 10% extra tension for a few seconds before returning to the desired tension.
Constant-pull tensioningElectronic machines maintain tension throughout the stringing process, effectively prestretching the string by default.

⚙️ Effects on performance

  • Reduces tension loss: Helps strings maintain their tension longer, especially in the early hours of play.
  • Improves control: A more stable stringbed provides better feedback and precision.
  • Less power, more feel: Prestretched strings tend to feel slightly stiffer but more accurate.
  • Shorter break-in period: The racquet reaches its "true" feel more quickly after stringing.

🎯 In practice

Prestretching is especially recommended for polyester strings, which suffer from high initial tension loss. Players looking for consistency and durability often prefer prestretching. However, for natural gut or multifilament strings, it's usually avoided, as it may reduce comfort and increase the risk of breakage. Always consider your playing style, string type, and personal preference before deciding to prestretch.


Measurement system