Measure around the widest part of your head, about an inch above your eyebrows. Sizes vary by model: the Ultra comes in S (51–55 cm), M/L (54–61 cm), and XL (61–65 cm). The Nyxel comes in S (52–56 cm), M (55–59 cm), and L (58–63 cm), with a redesigned headform for a more precise fit. Full size charts are on each product page.
Certifications vary by model and market. Across the range, Lumos helmets are tested against standards including CPSC (US), CE EN1078 (EU), and ASTM F1447, with the Ultra, Ultra E-Bike, and Nyxel also carrying independent verification from TÜV. The Ultra E-Bike additionally holds NTA 8776 for higher-speed e-bike use and AS2063. MIPS — a low-friction layer that helps reduce rotational forces during angled impacts — is available on every adult model (Ultra, Nyxel, Ultra E-Bike, and Aero GT). Exact certifications for each model are listed on its product page.
All current commuter and e-bike models charge via USB-C and are designed for wet-weather commuting. The Ultra E-Bike explicitly lists IPX6 water resistance, and Lumos does not recommend rinsing or showering the helmet directly. Run times depend on lighting mode: the Ultra and Ultra E-Bike last up to 10 hours on a roughly 3-hour charge, and the Nyxel runs 3.5–14 hours on about a 4-hour charge.
One-year limited warranty from the date of purchase, covering manufacturing defects in materials and workmanship. Registering your helmet within 30 days starts the warranty from the registration date. Battery life concerns are not covered, as run time varies with usage.
Any helmet involved in a crash should be replaced, even if it looks fine — the protective foam may be compressed. Our Accident Replacement Program offers a discounted replacement (based on MSRP) for helmets purchased from lumoshelmet.co, our official Amazon store, or our Kickstarter campaigns within the last two years. You'll need photos of the damage, the serial number (on the white sticker inside), a description of the accident, and proof of purchase. Each helmet is eligible once, and upgrades to different models are not available through the program.