String comparison
RPM Blast vs Black Code
Babolat RPM Blast against Tecnifibre Black Code: ratings, specs and which one fits your junior.
The short answer
Both are polyester strings. RPM Blast leads on spin and control. Black Code leads on comfort, durability and tension hold. 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 RPM Blast if…
- You want more spin (10 vs 8 out of 10)
- You want more control (9 vs 8 out of 10)
- Best for: heavy topspin players
- Best for: advanced juniors with fast, full swings
- Best for: players who generate their own power
Pick Black Code if…
- You want more comfort (7 vs 5 out of 10)
- You want more durability (8 vs 7 out of 10)
- You want more tension hold (6 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 $20 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 | RPM Blast | Black Code |
|---|---|---|
| Type | Polyester | Polyester |
| Construction | Octagonal high-density co-polyester monofilament | Pentagonal co-polyester with Thermocore technology |
| Gauges | 16, 17, 18 | 16, 17, 18 |
| Stiffness | Medium high | Medium |
| Set price | $20–21 | $12–16 |
| Reel price | $130–150 | $130–160 |
| Arm friendliness | 2/5 · Low | 3/5 · Moderate |
| Cost to maintain | 3/5 | 4/5 |
| Recommended from | Age 14 | Age 13 |
| Levels | Advanced, Elite | Intermediate, Advanced |
| Play styles | Baseliner, Big hitter | Baseliner, Big hitter |
| Junior tension | 46-50 lbs for juniors. String lower to unlock spin potential. Loses tension quickly so some players string 2-3 lbs higher. | 48-52 lbs for juniors. |
RPM Blast in short
Babolat RPM Blast is one of the most iconic co-polyester strings ever made. When Rafael Nadal showed up at the 2010 Australian Open with this octagonally shaped co-poly, it changed the game. The octagonal structure with high-density co-polyester adds phenomenal rotation to the ball. The slick surface enables the strings to snap back with vicious force, resulting in extra RPMs. One of the most popular co-polys of all time, this firm and durable string is perfect for big hitters looking to load the ball with pace and spin.
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.
RPM Blast vs Black Code: quick answers
Which has more spin, RPM Blast or Black Code?
Babolat RPM Blast, with a spin rating of 10/10 against 8/10.
Which is more arm-friendly for a junior?
Tecnifibre Black Code scores 3/5 for arm friendliness, against 2/5 for RPM Blast. It is recommended from age 13.
Which lasts longer?
Tecnifibre Black Code rates 8/10 for durability against 7/10.
Which is cheaper?
RPM Blast costs about $20–21 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 (RPM Blast) and 2025-01 (Black Code).