String comparison
4G vs Black Code
Luxilon 4G against Tecnifibre Black Code: ratings, specs and which one fits your junior.
The short answer
Both are polyester strings. 4G leads on control, durability and tension hold. Black Code leads on comfort. For a junior with arm concerns, Black Code is the safer choice. Black Code costs less per set.
Ratings
Power
Spin
Control
Comfort
Durability
Tension hold
Ratings are on a 1–10 scale. The higher score is in bold when they differ.
Pick 4G if…
- You want more control (9 vs 8 out of 10)
- You want more durability (9 vs 8 out of 10)
- You want more tension hold (10 vs 6 out of 10)
- Best for: control-oriented advanced juniors
- Best for: players who hate restringing frequently
- Best for: players who value precision over power
Pick Black Code if…
- You want more comfort (7 vs 5 out of 10)
- Arm comfort comes first (arm friendliness 3/5 vs 2/5)
- Your player is younger (recommended from age 13 vs 14)
- You want to spend less (from $12 vs $21 a set)
- Best for: aggressive baseliners who control points with heavy spin
- Best for: players wanting shaped poly comfort
- Best for: big hitters who swing hard
Specs side by side
| Spec | 4G | Black Code |
|---|---|---|
| Type | Polyester | Polyester |
| Construction | Co-polyester monofilament with poly-ether-ether compound | Pentagonal co-polyester with Thermocore technology |
| Gauges | 16, 16L | 16, 17, 18 |
| Stiffness | High | Medium |
| Set price | $21–22 | $12–16 |
| Reel price | $170–200 | $130–160 |
| Arm friendliness | 2/5 · Low | 3/5 · Moderate |
| Cost to maintain | 4/5 | 4/5 |
| Recommended from | Age 14 | Age 13 |
| Levels | Advanced, Elite | Intermediate, Advanced |
| Play styles | Baseliner, All court | Baseliner, Big hitter |
| Junior tension | 48-52 lbs for juniors. Better tension maintenance means more consistent feel over time. | 48-52 lbs for juniors. |
4G in short
Luxilon 4G was designed with one goal: better tension maintenance than ALU Power. Made with Luxilon's magical poly-ether-ether compound, 4G strings feature best-in-class durability, control and tension maintenance. Unlike many polys that go dead after 8-10 hours, 4G keeps its feel and control far longer. Its tension holding score of 100% isn't marketing hype - it's backed up by lab data. Control is where 4G shines, making it a workhorse that's reliable, consistent, and built for precision.
Black Code in short
Tecnifibre Black Code is a co-poly with pentagonal profile for spin and Thermocore technology for comfort. "Dangerous in the hands of an aggressive baseliner who likes to control the point with heavy spin." The 5-sided profile provides powerful snapback for spin generation while Thermocore uses heating and cooling phases to soften the string. Playtesters found it "soft, plush and very comfortable for a polyester string" with muted impact feel that doesn't send jarring vibrations on off-center hits. Great value shaped poly.
4G vs Black Code: quick answers
Which has more spin, 4G or Black Code?
They tie on our spin rating (8/10 each).
Which is more arm-friendly for a junior?
Tecnifibre Black Code scores 3/5 for arm friendliness, against 2/5 for 4G. It is recommended from age 13.
Which lasts longer?
Luxilon 4G rates 9/10 for durability against 8/10.
Which is cheaper?
4G costs about $21–22 a set and Black Code about $12–16, at typical retail.
The short answer and the "pick if" lists are generated from our ratings and junior data only. Data verified 2025-01 (4G) and 2025-01 (Black Code).