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Gauge guide

Thicker lasts. Thinner bites.

Gauge is string diameter. US sizes (15L, 16, 16L, 17, 18) map to millimeters. Small differences change durability, spin potential, and feel.

Tennis racket strings close-up

Common gauges (approx.)

US gaugeApprox. mmTypical tradeoff
15L~1.35–1.40Very durable, less bite
16~1.30Durability-first club default
16L~1.25–1.28Balance of life + spin (e.g. Hyper-G 16L)
17~1.20–1.25More spin/feel, shorter life (e.g. NXT 17, RPM 17)
18~1.10–1.20Max feel/bite; breaks sooner (e.g. Poly Tour Pro 18)

Always confirm the mm printed on the package — brand labeling varies slightly. Our product cards list the gauge as sold on the verified ASIN.

How to use gauge in practice

Verified examples on this site

Solinco Hyper-G 16L

Solinco Hyper-G 16L (1.25)

16LPoly

Shaped poly at 1.25 mm — spin with usable life.

$13.99 / set

Price as of Aug 28, 2026 · Amazon may change

ASIN B0170OYCPC · Affiliate link

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Wilson NXT 17

Wilson NXT 17

17Multi

Thinner multi for snap and comfort.

$23.95 / set

Price as of Aug 28, 2026 · Amazon may change

ASIN B015TJ1W6M · Affiliate link

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Yonex Poly Tour Pro 18

Yonex Poly Tour Pro 18 (1.15)

18Poly

Thin poly for bite and touch.

$23.00 / set

Price as of Aug 28, 2026 · Amazon may change

ASIN B0893GR2Z5 · Affiliate link

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Luxilon ALU Power 125

Luxilon ALU Power 125

1.25Poly

Tour co-poly reference at 1.25 mm.

$21.50 / set

Price as of Aug 28, 2026 · Amazon may change

ASIN B001EHEJ1Y · Affiliate link

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Mobile Racket — Wake County, North Carolina only Book a professional restring at mobileracket.com. Service area is Wake County, NC only (not nationwide). Bring a closed / sealed (unopened) set for $20 BYO labor — separate from Diadem-included $35 / $45 / $65 packages. Wake County, North Carolina only

FAQ — gauge

Is 16L the same as 1.25?

Often close, but not a legal identity — check the mm on the specific pack. Our Hyper-G card is listed as 16L (1.25) from the verified Amazon listing.

Should juniors use thicker string?

Comfort and swing speed matter more than copying adult gauges. Many juniors do well with multi in a mid gauge; ask Mobile Racket when you book (Wake County NC).