StringSpec
String finder

Browse all 789

Babolat

RPM Blast 18 (1.20)

Polyester Gauge 18 1.32 mm In production

Lab measurements for Babolat RPM Blast 18 (1.20), ranked against all 789 strings in the database. Every figure below is a testing-machine result at a fixed reference tension, not a playtest opinion.

Measured values

Stiffness

189lb/in

lower = softer, kinder on the arm

Tension loss

36%

lower = stays where you strung it

Energy return

87%

higher = livelier, more free power

Spin potential

5.1

higher = more spin off the string bed

Ball bite

0.391COF

higher = grabs the ball harder

Snapback

0.076COF

lower = strings slide and snap back

How it ranks against all 789 strings

Stiffness 189 lb/in · 57th pct

Stiffer than 57% of strings tested.

Tension loss 36 % · 60th pct

Sheds more tension than 60% of strings tested.

Energy return 87 % · 41st pct

Livelier than 41% of strings tested.

Spin potential 5.1 · 59th pct

More spin potential than 59% of strings tested.

Ball bite 0.391 COF · 18th pct

Grips the ball harder than 18% of strings tested.

Snapback 0.076 COF · 15th pct

More string-on-string friction than 15% of strings tested.

Strings that play like this

Closest matches across stiffness, tension loss, energy return and spin potential.

Topspin Cyber Blue 17L (1.20) 97% match Dunlop Black Widow 16 97% match Yonex Poly Tour Pro 17 (1.20) 96% match RS RS Lyon 17L (1.20) 96% match Dunlop Explosive 17 (1.26) 96% match SuperString Viper V2 Rough 16L 95% match

More from Babolat

What these numbers mean

Stiffness · lb/in

How much the string bed resists deflection. Higher plays firmer and more controlled; lower plays softer and easier on the arm.

Tension loss · %

Share of the reference tension the string sheds under a fixed test protocol. Lower means the bed stays where you strung it for longer.

Energy return · %

Share of impact energy handed back to the ball. Higher plays livelier and more powerful.

Spin potential

Ball friction divided by string-on-string friction. Higher means better bite with a cleaner snapback, so more spin.

Ball bite · COF

String-on-ball friction. Higher grabs the ball harder through the brush.

Snapback · COF

String-on-string friction. Lower lets the mains slide and snap back into place after impact.

Compare RPM Blast 18 (1.20) against 789 strings Find the right string for me