SCHUBERTH C4 Manuel page 66

C. THE HELMET
Note:
To avoid scratching the face schield, never remove or fit the anti-fog lens
unless the visor unit is clean and dry.
When fitting the anti-fog lens, check that neither dust nor moisture are
able to get between the two surfaces.
When removing or fitting the anti-fog lens, it is always best to lay the face
schield unit on a clean, dry cloth.
Note:
In view of the strong air pressure acting when travelling with an open
face shield, we recommend riding with a closed face schield at all times to
prevent any dirt or moisture from getting inside the helmet.
Note:
Never press the locking pins out with your fingers as they may break.
Caution:
As a result of the double lens structure, there is a possibility of greater
light reflection in the face schield, especially when riding at night. As a
rule, such light reflection is regarded as uncritical due to the absence of
fog with this type of visor. However, if this light reflection should cause
you difficulties – because of particular sensitivity to it, for example – you
should refrain from using the anti-fog lens.
Caution:
If moisture is present in or has penetrated the airtight area between the
two plates, you should remove the anti-fog lens immediately in order to
prevent any interference with visibility. Do not re-fit it until both plates are
completely dry (we recommend air-drying). If you should subsequently
detect any further penetration of moisture, the anti-fog lens should not be
used on any account and must be replaced.
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