Expert Guide to ReString Slap and Babolat RPM Blast

Both ReString Slap and Babolat RPM Blast are shaped, black polyester strings built for spin-oriented players. They target a similar audience and look nearly identical in a bag, but the technology under the surface tells a very different story.

RPM Blast pioneered the slippery, spin-first polyester era when it launched around 2010. ReString Slap represents what that idea looks like fifteen years later, with Signature Snapback technology that keeps the stringbed playing fresh for longer.

This article compares both strings and helps you choose the right one for your game.

String Performance

ReString Slap Overview

ReString Slap is a hexagonal co-polyester string designed for aggressive baseliners who want spin, power, and snapback that lasts. It carries ReString's Signature Snapback coating and a sharp six-sided profile built to grip the ball on every stroke.

The biggest distinction between ReString Slap and a string like RPM Blast comes down to how the coating works. ReString's Signature Snapback coating is integrated into the string's formulation rather than applied as an external layer.

This means snapback, spin, and feel remain consistent across the string's lifespan rather than degrading as a surface layer wears away, causing the string to play dead over time.

The shaped profile of ReString Slap bites into the ball on every stroke, generating heavy topspin with committed swings. If you take full cuts at the ball, the hexagonal shape rewards that aggression with high-RPM spin and sharp angles.

Despite the spin and power on offer, Slap is not a wild string. It delivers a plush feel at contact with enough control and forgiveness to keep big shots on the court.

If you are familiar with how ReString Zero plays, then ReString Slap is its more composed cousin.

ReString Slap is available in 17G (1.23mm) and 16G (1.28mm). We recommend stringing 2 lbs lower than your usual poly setup to maximize the snapback and playability benefits.

All sets are sustainably packaged in FSC-certified recycled paper, and ReString operates as a carbon-neutral business.

Babolat RPM Blast Overview

RPM Blast is an octagonal co-polyester string launched around 2010.

It was one of the first strings to place a premium on snapback through a silicone oil surface coating, and it quickly became a benchmark in the spin poly category.

The coating is an outer layer applied to the string's surface. Over time, this surface layer wears off, leading to reduced snapback and spin generation as the string ages.

The product has remained essentially unchanged since launch, using the same surface-coating technology.

Tension maintenance is a commonly noted characteristic in player feedback. Performance tends to drop once the coating wears and notching sets in, which shortens the window where the string feels and plays at its best.

RPM Blast is available in 15L (1.35mm), 16G (1.30mm), 17G (1.25mm), and 18G (1.20mm).

It is part of a broader RPM family that includes RPM Blast Rough, RPM Power, RPM Soft, and RPM Team, but RPM Blast remains the flagship.

Before ReString Slap was released, many RPM Blast players had already transitioned to ReString Zero over the years for better tension maintenance, which we covered in detail in another article.

Which String Should You Choose?

Choose ReString Slap if you want a modern spin polyester with integrated snapback technology that maintains its fresh feel session after session.

Players currently enjoying RPM Blast will find a similar experience in terms of shape, power, and ball action, with the added benefit of longer-lasting snapback and playability.

Choose RPM Blast if you prefer the familiarity of a widely available legacy spin polyester and are comfortable with a shorter peak performance window.

About the Author: Juan is the co-founder of ReString. He was born in Argentina, raised in Japan, and moved to the US to pursue college tennis. He now plays as an ATP & WTA hitting partner.