Sigma-II Compact Aerodynamic Cycling Helmet

• Lightweight (M) 225g
• Windtunnel Tested
• Washable liner
• Integrated magnetic visor attachement
• 18 Open Vents
• Single thickness | 1-piece liner with bug shield
• Extra 5-piece liner set included for enhanced ventilation
• Inmold EPC/PC construction
• CE, EN1078 certification
• Approved For Racing in ITU triathlon, UCI cycling, World Skate (FIRS)
• Standard buckle clip
• Dial-Ratchet Lock Fit System
• Vertical adjustment option

The Sigma-II is a compact aero helmet built for cyclists and triathletes who want a lightweight, streamlined shell without extra bulk.

COMPACT AERODYNAMIC SHAPING

A minimalist shell profile reduces frontal area while keeping the helmet light on long rides — the kind of aero helmet triathlon and road cyclists can wear from warm-up through race finish.

MAGNETIC VISOR COMPATIBILITY

A hidden magnetic attachment system pairs the Sigma-II with Cádomotus SKY or A2 lenses, so you can flip the visor up and stow it in seconds without fumbling for buckles mid-ride.

VENTILATION AND COMFORT

Vent channels manage airflow across the shell, helping regulate temperature through training blocks and races without adding weight to the compact design.

WHO IT'S FOR

Cádomotus built the Sigma-II for cyclists and triathletes who want one aero helmet for training and racing — compact, lightweight, and ready for a magnetic visor when conditions call for it.

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