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Tecnifibre · Multifilament

Tecnifibre X-One Biphase

High Heat Capacity (H2C) fibers with Biphasic trimerization process and polyurethane immersion

Log this string Compare Data verified January 2025
Price per set$18–22USD, typical retail
Gauges16, 17, 18Natural, Red
StiffnesslowMultifilament
Junior minimum age8+beginner, intermediate, advanced

Performance ratings

Power 9
Spin 5
Control 6
Comfort 10
Durability 5
Tension hold 7

Overview

X-One Biphase is Tecnifibre's premium multifilament that combines their best technologies into a single string. The patented Biphasic process with visible marks extends string life by 20% while the H2C fibers allow extreme temperature treatment during manufacturing. Multifilament fibers are immersed in polyurethane for shock absorption and optimum comfort. Many users say "I've never tried natural gut, but X-One Biphase is what I imagine it would feel like." Easily one of the more powerful multifilaments available with cloud-like comfort even at higher tensions.

Best for

  • Players wanting natural gut feel without gut price
  • Those with arm issues or tennis elbow
  • Flat hitters with slow to medium swing speeds
  • Hybrid crosses with poly mains
  • Touch players seeking maximum feel

Not ideal for

  • Heavy topspin players
  • String breakers
  • Those needing maximum control
  • Big hitters with fast swings (may overhit)

Pros

  • Closest to natural gut feel
  • Exceptional comfort - ideal for tennis elbow
  • Outstanding power generation
  • Good tension maintenance for multifilament
  • Biphasic process extends life 20%
  • Premium French manufacturing

Cons

  • Limited spin potential
  • Not for big hitters who need control
  • Frays relatively quickly (normal for multi)
  • Premium price
  • Power can cause overhitting

Stringer notes

Handle carefully like all multifilaments. Great as hybrid crosses. The visible biphasic marks are normal. Lasts 3-5 hours longer than other multis.

Break-in period

Minimal. Settles in nicely.

When to replace

Every 12-18 hours or when fraying becomes excessive.

Hybrid setup ideas

  • Poly mains + X-One Biphase crosses (Djokovic used this setup)
  • Works beautifully as full bed for comfort seekers
  • RPM Blast mains + X-One crosses for spin + comfort

Used by

Novak Djokovic (formerly, in hybrid), Many recreational and senior players

Specifications

Type
Multifilament
Construction
High Heat Capacity (H2C) fibers with Biphasic trimerization process and polyurethane immersion
Gauges
16, 17, 18
Colors
Natural, Red
Set price
$18–$22
Reel price
$200–$250
Brand
Tecnifibre (France)

Sources & reviews

Data verified January 2025. Something wrong? Send a correction.

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