Komatsu PC308USLC-3E0 Operation & Maintenance Manual page 110

OPERATION
DETAILED CONTROLS AND GAUGES
Vent Selector Switch (Air Flow to Upper Part of Body and Foot)
If this switch (1) is pressed, the air from the air conditioner is
directed to the face and feet.
Vent Selector Switch (Air Flow to Foot)
If switch (1) is pressed, the air from the air conditioner is all directed
to the feet.
This can be used to send warm air to the feet during cold weather.
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