Expert Guide to reString Sync and Toroline A5

Both reString Sync and Toroline A5 are round co-polyester strings built for players who value control, feel, and snapback over raw power.

They are the two newest rivals targeting the control string space established by Luxilon ALU Power.

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

String Performance

reString Sync Overview

reString Sync is a round co-polyester designed to deliver excellent control, precision, and connection with your shots.

Spin comes entirely through its Signature Snapback technology. We rate Sync a 9 out of 10 for spin on our scorecard, which is a strong output for a string with no shaped edges.

Compared with traditional polyesters, reString Sync is engineered to play better for longer. This is achieved by our Signature Snapback technology and tension maintenance.

Both of these work together, so the connected response you get from a fresh stringbed holds up across sessions rather than fading after a few hits.

reString Sync comes in three gauges, 18G / 1.20, 17G / 1.25, and 16G / 1.30.

That range gives you real flexibility to tune the string to your game, whether you want more feel from a thinner gauge or more durability from a thicker one.

We recommend stringing reString Sync 2 lbs lower than your usual polyester setup to maximize the snapback and playability benefits.

Every set is packaged responsibly in FSC sourced biodegradable and recycled paper, and 100% of carbon emissions are certified offset.

Toroline A5 Overview

Toroline A5 is a round carbon gray co-polyester that launched in April 2026, making it one of the newest strings on the market.

Toroline states that A5, similar to reString Sync, is built for precision and spin. It achieves its precision through its round profile and its spin through snapback.

It comes in a single gauge, 17G / 1.25, priced at $17.00 per set. That price point fits a broader pattern at Toroline, where older strings sit at $12 while newer launches arrive at higher prices.

For more context, Tennisnerd has compared Toroline A5 and reString Sync directly. In his experience, A5 plays a bit softer, while reString Sync delivers better control.

Comparison with ALU Power

Both reString Sync and Toroline A5 are chasing the same target.

Luxilon ALU Power remains one of the most popular round strings in the game, used by plenty of top 100 players on the pro tour today.

However, where ALU Power falls short is snapback and tension maintenance. Both reString Sync and Toroline A5 improve on this.

Tennisnerd has compared Toroline A5 to ALU Power and said it has more snapback and spin potential, which mirrors how players describe reString Sync compared to ALU Power.

Where we believe reString Sync goes further than Toroline A5 is with the specific engineering to play better for longer with its Signature Snapback and strong tension maintenance.

Which String Should You Choose?

Choose reString Sync if you want a control-first round string with tour-level spin thanks to our Signature Snapback technology, strong tension maintenance, three gauge options, and a slightly lower price.

Choose Toroline A5 if you want a slightly softer round string, snapback-driven spin generation, and are happy with a single 1.25 gauge.

If you are still unsure, our String Finder helps you find the right setup for your game.

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.