Honda EU30is Owner's Manual page 56

Installation:
1. Make sure that the engine switch is turned OFF.
2. Connect the battery positive (+) cable to the battery positive (+) terminal,
then the battery negative (–) cable to the battery negative (–) terminal.
Tighten the bolts and nuts securely.
3. Install the battery rubber and the battery holder band.
4. Install the front cover, and install the four 6 mm cap nuts.
CAUTION:
When disconnecting the battery cable, be sure to disconnect at the battery
negative (–) terminal first. To connect, connect at the positive (+) terminal
first, then at the negative (–) terminal. Never dis/connect the battery cable
in the reverse order, or it causes a short circuit when a tool contacts the
terminals.
This symbol on the battery means that this product must not be
treated as household waste.
NOTE:
An improperly disposed of battery can be harmful to the environment and
human health.
Always confirm local regulations for battery disposal.
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