$10-13 Per Set
16, 17, 18 Gauges
medium Stiffness
12+ Min Age

Performance Ratings

power 7/10
spin 7/10
control 8/10
comfort 6/10
durability 8/10
tension Maintenance 8/10

Junior Player Guide

For Parents
Arm Friendliness Moderate
Cost Effectiveness Great value

Recommended Level

intermediateadvancedelite

Tension for Juniors

50-54 lbs for juniors. Pre-stretched for better tension maintenance.

Gauge Recommendation

17 (1.25mm) for best feel and spin balance.

Overview

Kirschbaum Pro Line II is one of the softest and most responsive co-polyester strings available. Built on 20+ years of German polyester expertise from the company that pioneered polyester tennis strings, Pro Line II offers better pocketing and a more forgiving feel on off-center impacts compared to traditional polyesters. The pre-stretch treatment ensures consistent playability with precise and predictable response, enabling players to swing bigger when going for pace and spin.

Best For

  • Players wanting soft, responsive poly
  • All-court players seeking versatility
  • Those who want poly control with better feel
  • Tournament players on a budget

Not Ideal For

  • Players with serious arm issues
  • Those seeking maximum spin
  • Players wanting ultra-crisp response

Pros

  • + Soft and responsive for a poly
  • + Pre-stretched for tension maintenance
  • + Good pocketing and forgiveness
  • + Predictable, precise response
  • + Excellent value
  • + Used by Grand Slam champion Angelique Kerber

Cons

  • Not the most spin-friendly
  • Round profile limits bite
  • Still a poly - not for arm issues

Specifications

Type polyester
Construction Round co-polyester monofilament with pre-stretch treatment
Gauges 16, 17, 18
Colors Black
Set Price $10-$13
Reel Price $90-$110

Used By

Angelique Kerber (former)Jan-Lennard StruffCarlos Moya (former)Vera Zvonareva

Hybrid Setup Ideas

  • Kirschbaum Touch Multifibre crosses
  • Wilson NXT crosses for comfort
  • Natural gut mains for premium feel

Stringer Notes

Pre-stretched - ready to install. Great tension stability. One of softest polys available.

Break-in Period

Minimal due to pre-stretch treatment.

When to Replace

Every 15-20 hours or when feel becomes mushy.

Sources

Data verified January 2025

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