String comparison
RPM Blast vs Plasma HEXtreme
Babolat RPM Blast against Signum Pro Plasma HEXtreme: ratings, specs and which one fits your junior.
The short answer
Both are polyester strings. RPM Blast leads on spin and control. Plasma HEXtreme leads on tension hold. They score the same for arm friendliness (2/5). Plasma HEXtreme 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 9 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 Plasma HEXtreme if…
- You want more tension hold (8 vs 5 out of 10)
- Your player is younger (recommended from age 13 vs 14)
- You want to spend less (from $10 vs $20 a set)
- Best for: maximum spin seekers
- Best for: heavy topspin baseliners
- Best for: players with western grips
Specs side by side
| Spec | RPM Blast | Plasma HEXtreme |
|---|---|---|
| Type | Polyester | Polyester |
| Construction | Octagonal high-density co-polyester monofilament | Hexagonal co-polyester monofilament |
| Gauges | 16, 17, 18 | 16L, 17, 18 |
| Stiffness | Medium high | Medium high |
| Set price | $20–21 | $10–13 |
| Reel price | $130–150 | $120–145 |
| Arm friendliness | 2/5 · Low | 2/5 · Low |
| Cost to maintain | 3/5 | 4/5 |
| Recommended from | Age 14 | Age 13 |
| Levels | Advanced, Elite | Intermediate, Advanced, Elite |
| 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. Hex shape grabs ball - can string lower. |
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.
Plasma HEXtreme in short
Signum Pro Plasma HEXtreme was one of the first hexagonal shaped strings on the market, pioneering the shaped poly category that has become so popular. The six edges provide excellent ball bite for spin generation while maintaining the tension stability Signum Pro is known for. Built on the proven Plasma foundation with enhanced spin potential, HEXtreme offers German engineering in a modern spin-focused design.
RPM Blast vs Plasma HEXtreme: quick answers
Which has more spin, RPM Blast or Plasma HEXtreme?
Babolat RPM Blast, with a spin rating of 10/10 against 9/10.
Which is more arm-friendly for a junior?
They score the same, 2/5. RPM Blast is recommended from age 14 and Plasma HEXtreme from age 13.
Which lasts longer?
They tie on durability (7/10). Tension maintenance: RPM Blast 5/10, Plasma HEXtreme 8/10.
Which is cheaper?
RPM Blast costs about $20–21 a set and Plasma HEXtreme about $10–13, 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 (Plasma HEXtreme).