Honda HS1810Z Owner's Manual page 28

Backward stop lever
When the snowblower goes backward, it snowblower can be slowed
down and stopped by using the backward stop lever.
If the backward stop lever is pushed, the shift lever will be returned in
the direction of the ''NEUTRAL'' position and the backward speed will
slow down and stop.
Furthermore if the backward stop lever is pushed as far forward as it
will go, the snowblower will move forward.
When you stop the snowblower completely, set the drive clutch
lever to the ''stop'' position.
Since a backward stop lever is not a bumper, never ride and never
attach a rope. It can cause a failure.
SHIFT LEVER
NEUTRAL
BACKWARD STOP LEVER
PUSH
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