Pre-Stretch
The pre-stretch of the core minimises tension loss and allows stringing at lower tensions.
Arm Friendly®
String Project Armour
Plush on impact, precise off the strings.
String Project Armour is a co-polyester competition monofilament tennis string (Soft Polyester + High-Density Polyester HDC), designed for players who want ball feel and control. High-Density Polyester provides impact consistency, while the smooth surface promotes good snap-back. Arm Friendly®, with 8/10 comfort.
8/10
Comfort
9/10
Spin
7.5/10
Power
Technical Specifications and On-Court Ratings
Competition Feel and Total Control
String Project Armour delivers competition-level control (8.5/10), letting you place every shot with precision and confidence. Spin (9/10) comes from good snap-back and, above all, from the string's plush feel: the ball stays on the string bed longer and, with the right swing, comes off loaded with rotation. Power (7.5/10) is contained and calibrated, ideal for those who prefer to build the point with tactical intelligence rather than brute force.
Power7.5/10
Comfort8/10
Control8.5/10
Resilience8/10
Spin9/10
Tension8.5/10
Ratings measured in the laboratory by Pro-t-one (Eng. G. Medri), as are the technical specifications.
"Arm Friendly®" Technology: Comfort Without Compromise
The co-polyester composition balances Soft Polyester and High-Density Polyester (HDC). Soft Polyester ensures softness and vibration absorption, while High-Density Polyester provides structural stiffness, impact consistency and long-term durability. The smooth surface of the round cross-section contributes to a clean, predictable snap-back.
Technical Data Sheet
- Cross-section
- Round
- Available gauges
- 1.25 (16L) · 1.32 (15L)
- Dynamic stiffness
- 225 g/mm
- String Stiffness Emulator
- 220 lb/in
- Static stiffness
- 0.88 kg/mm
- Tension range
- 18 / 22 Kg
Laboratory test report · Pro-t-one (Eng. G. Medri)
Competition Technology and Composition
String Project Armour is made of co-polyester, with two materials working together. Soft Polyester brings softness and vibration absorption, and makes the string Arm Friendly®. High-Density Polyester (HDC) brings structural stiffness, impact consistency and long-term durability. The round cross-section, with its smooth surface, completes the profile with a clean, predictable snap-back.
The manufacturing processes
Double Heating
The heat treatments remove internal stresses and any irregularities in the string, making it more uniform, flexible and elastic.
Liquid Wax
The string is finished with a layer of wax, which reduces wear, significantly extends its lifespan and makes stringing easier.
Low Friction
Reducing friction offers three advantages: less string movement, greater spin potential thanks to better snap-back, and a longer lifespan.
Armour on Court: Solid and Plush
On court, Armour offers a solid impact that instils confidence in every shot, together with a plush feel that keeps the ball on the string bed longer. Power is manageable, allowing you to meter force with precision. Despite its robustness, Armour offers remarkable comfort, absorbing vibrations and protecting the arm.
Plush Impact, Competition Control
Armour offers competition-level control (8.5/10), with a plush, communicative impact: the ball stays on the string bed just long enough for you to feel it and direct it. Impact consistency, provided by High-Density Polyester, lets you build the point with tactical precision.
- Plush, communicative impact
- Excellent impact consistency
- Precise directionality
- Tactical point construction
Spin Born from a Plush Feel
With 9/10 spin, Armour generates effective, natural rotation thanks to its plush feel: the string holds the ball an instant longer, so a player who brushes up with the right swing sends it off loaded with spin. The smooth surface and Low Friction treatments promote good snap-back, clean and predictable.
- Natural, consistent 9/10 spin
- Ball stays longer on the string bed
- Good, clean and predictable snap-back
- Heavy, controlled topspin
What the Experts Say
Independent reviews published by testers and specialist outlets.
Who It's For
Control-oriented competitors
Those who build the point with tactical intelligence and want a string with a plush impact and precise directionality on every shot.
Those seeking consistency
Those who want a string with solid, predictable impact that keeps its properties over time thanks to 8.5/10 tension maintenance and 8/10 resilience.
Those who want spin without giving up control
Those who generate spin as an integral part of their game but need rotation to be controlled, precise and repeatable.
Ready to Armour Up Your Game?
Choose the format that best suits your needs. Free shipping from €50.
200 m Reel
~17 stringings
-
~€6.41 per stringing
- Free shipping
- 1 Dampener
- 2x Dry Overgrip pack
Gauge:
Pack of 6 Sets
6 stringings
-
~€8.98 per stringing
- Free shipping
- 1 Dampener
- 2x Dry Overgrip pack
Gauge:
Pack of 3 Sets
3 stringings
-
~€9.97 per stringing
- Free shipping
- 1 Dampener
- 2x Dry Overgrip pack
Gauge:
Single Set
1 stringing
-
- Free shipping
- 1 Dampener
- 2x Dry Overgrip pack
Gauge:
Frequently Asked Questions (FAQ) about String Project Armour
What is String Project Armour?
String Project Armour is a co-polyester competition monofilament tennis string (Soft Polyester + High-Density Polyester HDC). It is engineered to deliver competition-level control (8.5/10) and spin (9/10) with Arm Friendly® comfort of 8/10.
At what tension should String Project Armour be strung?
The recommended tension range is between 18 and 22 kg. Lower tensions (18-19 kg) favour comfort and power, while higher tensions (21-22 kg) maximise control and directional precision.
Which gauges is String Project Armour available in?
Armour is available in two gauges: 1.25 mm (16L) for greater sensitivity and spin, and 1.32 mm (15L) for greater control, durability and impact consistency.
Is String Project Armour suitable for players with arm problems?
Yes, Armour is Arm Friendly®, with 8/10 comfort. Its co-polyester composition with Soft Polyester ensures good vibration absorption, while still being a performance-oriented competition string.
What is the difference between String Project Armour and String Project Hexa Pro?
Armour has a smooth round cross-section and is oriented towards feel and impact consistency, with 8.5/10 control and 9/10 spin. Hexa Pro has a hexagonal cross-section and is more oriented towards technical spin (9.5/10) and control (9/10). Armour has slightly lower dynamic stiffness (225 vs 230 g/mm).
How long does String Project Armour last?
Armour has 8.5/10 tension maintenance and 8/10 resilience, making it one of the most durable strings in the String Project range. The Liquid Wax treatment and Pre-Stretch technology help keep its properties consistent over time.