2 questions to find the right gear for you.
How long have you been doing water sports?


Duotone Windsurf
Variant
Unleash the full power of your quad wave board. Introducing the all‑new QUAD fin set — the ultimate choice for riders who demand nothing less than uncompromising performance from their quad‑fin wave boards. Designed by Kai Hopf and based on over 30 years of experience working with the best wave sailors in the world. Unlike generic “multi‑use” fin concepts, the QUAD set is engineered as a dedicated, no‑compromise quad system. Every outline, profile, and response characteristic has been purpose‑built for maximum control, drive, and agility in high‑performance wave conditions. This is the same design philosophy trusted—quietly but consistently—by many World Cup professionals who rely on Kai’s custom fins to stay ahead of the pack. Now, we’re making this top‑tier performance available to everyone.Shorter fins. Higher performance.Proof of their level of efficiency is the fact that our fins are 1–2 cm shorter than comparable quad sets. This is made possible through our exclusive AI_FIN CAD software, which achieves a flawless profile transition in the critical tip area where the fin sweeps backward. The result?Radically enhanced maneuverabilityGreat grip without being stickyInstant response in every turnPremium materials. Maximum precision.The center fin is CNC‑milled from black G10, an ultra‑dense, prepreg‑laminated fiberglass material renowned for:Outstanding durabilityExceptional impact resistanceEasy sandability to repair ground‑contact damageThis is the level of reliability and performance that serious wave sailors demand.Choosing the right sizeSelect your QUAD set according to the recommendations below. Oversized fins create excessive tail lift, making your board feel sticky and harder to turn. Proper sizing ensures your board performs exactly as intended—loose, fast, and precise.
| FIN | FIN SET QUAD 7.5 + 13.5 | FIN SET QUAD 8.0 + 14.0 | FIN SET QUAD 8.5 + 14.5 | FIN SET QUAD 9.0 + 15.0 | FIN SET QUAD 9.5 + 16.0 |
| LENGTH (CM) | 7.5 + 13.5 | 8.0 + 14.0 | 8.5 + 14.5 | 9.0 + 15.0 | 9.5 + 16.0 |
| BOX SYSTEM | SLOT | SLOT | SLOT | SLOT | SLOT | SLOT | SLOT | SLOT | SLOT | SLOT |
| TECHNOLOGY | BLACK G10 | BLACK G10 | BLACK G10 | BLACK G10 | BLACK G10 |
| DESIGNER | KAI HOPF | KAI HOPF | KAI HOPF | KAI HOPF | KAI HOPF |
| REC. BOARD TYPES | ANY QUAD WAVE BOARD | ANY QUAD WAVE BOARD | ANY QUAD WAVE BOARD | ANY QUAD WAVE BOARD | ANY QUAD WAVE BOARD |
| REC. BOARD SIZE (L) | 50-70 | 70-85 | 85-90 | 90-100 | 100-110 |
| REC. DUOTONE BOARD(S) | ULTRA GRIP QUAD 53+61+69 | ULTRA GRIP QUAD 76 + 82 | ULTRA GRIP QUAD 88 | ULTRA GRIP QUAD 94 | ULTRA GRIP QUAD 106 |