Size Chart Open Accordion
US SIZE EUR SIZE Length (cm)
5 37.7 23
5.5 38 23.5
6 38.5 24
6.5 39 24.5
7 39.5 25
7.5 40 25.5
8 41 26
8.5 41.5 26.5
9 42 27
9.5 42.5 27.5
10 43 28
10.5 44 28.5
11 44.5 29
11.5 45 29.5
12 46 30
12.5 46.5 30.5
13 47 31
14 49 32
15 50 32.5
Details Open Accordion

First introduced in 1989, the Si-18 International is an iconic representation of K-Swiss’ dedication to honoring athletic heritage while optimizing performance forfuture design. This reissue of the award-winning style combines elements of classic K-Swiss tennis, such as a premium leather upper, with innovative engineering that introduced the world to the ground breaking SiliconeFormula 18 for which the shoe is named. Flag accents adorn the heel and tongue to honor the host countries of the Grand Slam, the biggest tournament in tennis. Along with a vintage ski boot-inspired D-R Cinch lacing system and an asymmetric  single-densiy PU midsole, the Si-18 International Heritage provides unmatched comfortand support in a timelessly recognizable silhouette.The collaboration with Stadium brings back the Si-18 Premier as if it was vintage.The slightly off-white color gives the appealas if it has been sitting in a closet for decades. The colorway nods to Stadium’s own company colors while still looking like it was an actual retro color from the catalogs. Stadium respects the iconic look of the original Si-18 and really wanted to reimagine their own brand colors in the same heritage way.

  • Luxury white full-grain tumbled leather upper
  • Orange and green accents inspired by a classic tennis courts and summer, a season ripe for competitive tennis
  • Single density lightweight EVA midsole construction
  • Lightweight rubber outsole with the design DNA of the original shoe.
  • Signature gold plated D-R Cinch lacing system and heel stability counter for optimal support in lateral movement
  • TPU shank on the midfoot for stability and support
  • Premium leather upper for plush durability and style
  • Signature flag accents from four countries honoring the host countries of the biggest tournament in tennis
  • Lightly padded tongue and ankle collar for interior comfort and support for everyday wear
Shipping and Returns/Exchanges Open Accordion

SHIPPING will ship all orders Monday-Friday. All orders received with Two-Day Air by 10:30AM PST will ship the same business day, Monday through Friday. All Standard FedEx Ground orders will ship within 2 to 3 business days.

Note that all orders placed after 10:30AM PST on Fridays, Saturday or Sunday will not processed until the next business day.


We hope you love your K-Swiss product, but if you’re not completely satisfied, you can return or exchange merchandise within 30 days of purchase. Extended return/exchanges window may apply during holiday.