SCHUBERTH M1 PRO Manual page 8

A. FOR YOUR SAFETY
3. SAFETY ADVICE CONCERNING MODIFICATIONS/
ACCESSORIES
Original components (in particular on the outer shell, inner shell and
restraint system) should not be altered or removed. The fitting of additional
parts from other manufacturers that have not been recommended can
reduce the protective effect and renders the ECE certification and all
warranty and insurance claims invalid.
Use only original parts, replacement parts and accessories that
SCHUBERTH has expressly approved for your helmet!
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